Vulnerability-Lookup

BDU:2025-14699 (CVE-2025-40186)

Vulnerability from fstec – Published: 2025-11-26 – Updated: 2026-05-26 – View on bdu.fstec.ru Fixed

Title

Уязвимость функции reqsk_fastopen_remove() ядра операционной системы Linux, позволяющая нарушителю вызвать отказ в обслуживании

Summary

Уязвимость функции reqsk_fastopen_remove() ядра операционной системы Linux связана с использованием памяти после ее освобождения. Эксплуатация уязвимости может позволить нарушителю вызвать отказ в обслуживании

Severity

6.0 (Medium) CVSS 2.0


                      
                        AV:L/AC:H/Au:S/C:C/I:C/A:C

7.0 (High) CVSS 3.1


                      
                        CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

Class

Code vulnerability

Status

Confirmed by the vendor

Exploitation

Data structure manipulation, Resource manipulation

Incidents

Being clarified

Remediation

Software update

CWE

CWE-416 - Использование после освобождения
CWE-826 - Преждевременное освобождение ресурса в течение срока его эксплуатирования

Aliases

CVE-2025-40186

References

16 references

URL
https://lore.kernel.org/linux-cve-announce/2025111244-CVE-2025-40186-b204@gregkh/
https://git.kernel.org/stable/c/2e7cbbbe3d61c63606994b7ff73c72537afe2e1c
https://git.kernel.org/stable/c/422c1c173c39bbbae1e0eaaf8aefe40b2596233b
https://git.kernel.org/stable/c/643a94b0cf767325e953591c212be2eb826b9d7f
https://git.kernel.org/stable/c/64dc47a13aa3d9daf7cec29b44dca8e22a6aea15
https://git.kernel.org/stable/c/c11ace909e873118295e9eb22dc8c58b0b50eb32
https://git.kernel.org/stable/c/e359b742eac1eac75cff4e38ee2e8cea492acd9b
https://git.kernel.org/stable/c/eb85ad5f23268d64b037bfb545cbcba3752f90c7
https://git.kernel.org/stable/c/ff6a8883f96a5bc74241ce5b3d431a6dcfa2124d
https://security-tracker.debian.org/tracker/CVE-2025-40186
https://access.redhat.com/security/cve/cve-2025-40186
https://altsp.su/obnovleniya-bezopasnosti/
https://wiki.astralinux.ru/astra-linux-se18-bulletin-2026-0224SE18
https://wiki.astralinux.ru/astra-linux-se17-bulletin-2026-0302SE17MD
https://wiki.astralinux.ru/astra-linux-se38-bulletin-2026-0305SE38
https://wiki.astralinux.ru/astra-linux-se47-bulletin-2026-0518SE47

Impacted products

5 products from 5 vendors

Vendors

Red Hat, Inc., Сообщество свободного программного обеспечения, ООО «РусБИТех-Астра», АО «ИВК»

Products

Red Hat Enterprise Linux, Debian GNU/Linux, Astra Linux Special Edition (запись в едином реестре российских программ №369), Альт 8 СП (запись в едином реестре российских программ №4305), Linux

Versions

7 (Red Hat Enterprise Linux), 8 (Red Hat Enterprise Linux), 11 (Debian GNU/Linux), 12 (Debian GNU/Linux), 1.7 (Astra Linux Special Edition), 4.7 (Astra Linux Special Edition), - (Альт 8 СП), 9 (Red Hat Enterprise Linux), 1.8 (Astra Linux Special Edition), 10 (Red Hat Enterprise Linux), 13 (Debian GNU/Linux), до 6.18 rc1 (Linux), от 6.17 до 6.17.4 (Linux), от 5.4.300 до 5.4.301 (Linux), от 5.10.245 до 5.10.246 (Linux), от 5.15.194 до 5.15.195 (Linux), от 6.1.154 до 6.1.157 (Linux), от 6.6.108 до 6.6.113 (Linux), от 6.12.49 до 6.12.54 (Linux), 6.16.9 (Linux), 3.8 (Astra Linux Special Edition)

Product types

Operating system

Platforms

Red Hat, Inc. Red Hat Enterprise Linux 7, Inc. Red Hat Enterprise Linux 8, Сообщество свободного программного обеспечения Debian GNU/Linux 11, Сообщество свободного программного обеспечения Debian GNU/Linux 12, ООО «РусБИТех-Астра» Astra Linux Special Edition 1.7 (запись в едином реестре российских программ №369), ООО «РусБИТех-Астра» Astra Linux Special Edition 4.7 (запись в едином реестре российских программ №369), АО «ИВК» Альт 8 СП - (запись в едином реестре российских программ №4305), Inc. Red Hat Enterprise Linux 9, ООО «РусБИТех-Астра» Astra Linux Special Edition 1.8 (запись в едином реестре российских программ №369), Inc. Red Hat Enterprise Linux 10, Сообщество свободного программного обеспечения Debian GNU/Linux 13, Сообщество свободного программного обеспечения Linux до 6.18 rc1, Сообщество свободного программного обеспечения Linux от 6.17 до 6.17.4, Сообщество свободного программного обеспечения Linux от 5.4.300 до 5.4.301, Сообщество свободного программного обеспечения Linux от 5.10.245 до 5.10.246, Сообщество свободного программного обеспечения Linux от 5.15.194 до 5.15.195, Сообщество свободного программного обеспечения Linux от 6.1.154 до 6.1.157, Сообщество свободного программного обеспечения Linux от 6.6.108 до 6.6.113, Сообщество свободного программного обеспечения Linux от 6.12.49 до 6.12.54, Сообщество свободного программного обеспечения Linux 6.16.9, ООО «РусБИТех-Астра» Astra Linux Special Edition 3.8 (запись в едином реестре российских программ №369)

Mitigations

В условиях отсутствия обновлений безопасности от производителя рекомендуется придерживаться "Рекомендаций по безопасной настройке операционных систем LINUX", изложенных в методическом документе ФСТЭК России, утверждённом 25 декабря 2022 года. Использование рекомендаций: Для Linux: https://lore.kernel.org/linux-cve-announce/2025111244-CVE-2025-40186-b204@gregkh/ https://git.kernel.org/stable/c/2e7cbbbe3d61c63606994b7ff73c72537afe2e1c https://git.kernel.org/stable/c/422c1c173c39bbbae1e0eaaf8aefe40b2596233b https://git.kernel.org/stable/c/643a94b0cf767325e953591c212be2eb826b9d7f https://git.kernel.org/stable/c/64dc47a13aa3d9daf7cec29b44dca8e22a6aea15 https://git.kernel.org/stable/c/c11ace909e873118295e9eb22dc8c58b0b50eb32 https://git.kernel.org/stable/c/e359b742eac1eac75cff4e38ee2e8cea492acd9b https://git.kernel.org/stable/c/eb85ad5f23268d64b037bfb545cbcba3752f90c7 https://git.kernel.org/stable/c/ff6a8883f96a5bc74241ce5b3d431a6dcfa2124d Для Debian GNU/Linux: https://security-tracker.debian.org/tracker/CVE-2025-40186 Для программных продуктов Red Hat Inc.: https://access.redhat.com/security/cve/cve-2025-40186 Для ОС Альт 8 СП: установка обновления из публичного репозитория программного средства: https://altsp.su/obnovleniya-bezopasnosti/ Для ОС Astra Linux: - обновить пакет linux-6.1 до 6.1.158-1.astra1+ci8 или более высокой версии, используя рекомендации производителя: https://wiki.astralinux.ru/astra-linux-se18-bulletin-2026-0224SE18 - обновить пакет linux-6.12 до 6.12.60-1.astra1+ci20 или более высокой версии, используя рекомендации производителя: https://wiki.astralinux.ru/astra-linux-se18-bulletin-2026-0224SE18 Для ОС Astra Linux: - обновить пакет linux-5.10 до 5.10.248-1.astra1+ci7 или более высокой версии, используя рекомендации производителя: https://wiki.astralinux.ru/astra-linux-se17-bulletin-2026-0302SE17MD - обновить пакет linux-6.1 до 6.1.161-1.astra1 или более высокой версии, используя рекомендации производителя: https://wiki.astralinux.ru/astra-linux-se17-bulletin-2026-0302SE17MD Для ОС Astra Linux: обновить пакет linux-6.1 до 6.1.158-1.astra1+ci8 или более высокой версии, используя рекомендации производителя: https://wiki.astralinux.ru/astra-linux-se38-bulletin-2026-0305SE38 Для ОС Astra Linux: - обновить пакет linux-5.10 до 5.10.248-1.astra1+ci15 или более высокой версии, используя рекомендации производителя: https://wiki.astralinux.ru/astra-linux-se47-bulletin-2026-0518SE47 - обновить пакет linux-6.1 до 6.1.161-1.astra1+ci17 или более высокой версии, используя рекомендации производителя: https://wiki.astralinux.ru/astra-linux-se47-bulletin-2026-0518SE47

JSON

To clipboard

{
  "CVSS 2.0": "AV:L/AC:H/Au:S/C:C/I:C/A:C",
  "CVSS 3.0": "AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H",
  "CVSS 4.0": null,
  "remediation_\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440": null,
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  "\u0412\u0435\u043d\u0434\u043e\u0440 \u041f\u041e": "Red Hat, Inc., \u0421\u043e\u043e\u0431\u0449\u0435\u0441\u0442\u0432\u043e \u0441\u0432\u043e\u0431\u043e\u0434\u043d\u043e\u0433\u043e \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f, \u041e\u041e\u041e \u00ab\u0420\u0443\u0441\u0411\u0418\u0422\u0435\u0445-\u0410\u0441\u0442\u0440\u0430\u00bb, \u0410\u041e \u00ab\u0418\u0412\u041a\u00bb",
  "\u0412\u0435\u0440\u0441\u0438\u044f \u041f\u041e": "7 (Red Hat Enterprise Linux), 8 (Red Hat Enterprise Linux), 11 (Debian GNU/Linux), 12 (Debian GNU/Linux), 1.7 (Astra Linux Special Edition), 4.7 (Astra Linux Special Edition), - (\u0410\u043b\u044c\u0442 8 \u0421\u041f), 9 (Red Hat Enterprise Linux), 1.8 (Astra Linux Special Edition), 10 (Red Hat Enterprise Linux), 13 (Debian GNU/Linux), \u0434\u043e 6.18 rc1 (Linux), \u043e\u0442 6.17 \u0434\u043e 6.17.4 (Linux), \u043e\u0442 5.4.300 \u0434\u043e 5.4.301 (Linux), \u043e\u0442 5.10.245 \u0434\u043e 5.10.246 (Linux), \u043e\u0442 5.15.194 \u0434\u043e 5.15.195 (Linux), \u043e\u0442 6.1.154 \u0434\u043e 6.1.157 (Linux), \u043e\u0442 6.6.108 \u0434\u043e 6.6.113 (Linux), \u043e\u0442 6.12.49 \u0434\u043e 6.12.54 (Linux), 6.16.9 (Linux), 3.8 (Astra Linux Special Edition)",
  "\u0412\u043e\u0437\u043c\u043e\u0436\u043d\u044b\u0435 \u043c\u0435\u0440\u044b \u043f\u043e \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0438\u044e": "\u0412 \u0443\u0441\u043b\u043e\u0432\u0438\u044f\u0445 \u043e\u0442\u0441\u0443\u0442\u0441\u0442\u0432\u0438\u044f \u043e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u0439 \u0431\u0435\u0437\u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438 \u043e\u0442 \u043f\u0440\u043e\u0438\u0437\u0432\u043e\u0434\u0438\u0442\u0435\u043b\u044f \u0440\u0435\u043a\u043e\u043c\u0435\u043d\u0434\u0443\u0435\u0442\u0441\u044f \u043f\u0440\u0438\u0434\u0435\u0440\u0436\u0438\u0432\u0430\u0442\u044c\u0441\u044f \"\u0420\u0435\u043a\u043e\u043c\u0435\u043d\u0434\u0430\u0446\u0438\u0439 \u043f\u043e \u0431\u0435\u0437\u043e\u043f\u0430\u0441\u043d\u043e\u0439 \u043d\u0430\u0441\u0442\u0440\u043e\u0439\u043a\u0435 \u043e\u043f\u0435\u0440\u0430\u0446\u0438\u043e\u043d\u043d\u044b\u0445 \u0441\u0438\u0441\u0442\u0435\u043c LINUX\", \u0438\u0437\u043b\u043e\u0436\u0435\u043d\u043d\u044b\u0445 \u0432 \u043c\u0435\u0442\u043e\u0434\u0438\u0447\u0435\u0441\u043a\u043e\u043c \u0434\u043e\u043a\u0443\u043c\u0435\u043d\u0442\u0435 \u0424\u0421\u0422\u042d\u041a \u0420\u043e\u0441\u0441\u0438\u0438, \u0443\u0442\u0432\u0435\u0440\u0436\u0434\u0451\u043d\u043d\u043e\u043c 25 \u0434\u0435\u043a\u0430\u0431\u0440\u044f 2022 \u0433\u043e\u0434\u0430.\n\n\u0418\u0441\u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u043d\u0438\u0435 \u0440\u0435\u043a\u043e\u043c\u0435\u043d\u0434\u0430\u0446\u0438\u0439:\n\u0414\u043b\u044f Linux:\nhttps://lore.kernel.org/linux-cve-announce/2025111244-CVE-2025-40186-b204@gregkh/\nhttps://git.kernel.org/stable/c/2e7cbbbe3d61c63606994b7ff73c72537afe2e1c\t\nhttps://git.kernel.org/stable/c/422c1c173c39bbbae1e0eaaf8aefe40b2596233b\t\nhttps://git.kernel.org/stable/c/643a94b0cf767325e953591c212be2eb826b9d7f\t\nhttps://git.kernel.org/stable/c/64dc47a13aa3d9daf7cec29b44dca8e22a6aea15\t\nhttps://git.kernel.org/stable/c/c11ace909e873118295e9eb22dc8c58b0b50eb32\t\nhttps://git.kernel.org/stable/c/e359b742eac1eac75cff4e38ee2e8cea492acd9b\t\nhttps://git.kernel.org/stable/c/eb85ad5f23268d64b037bfb545cbcba3752f90c7\t\nhttps://git.kernel.org/stable/c/ff6a8883f96a5bc74241ce5b3d431a6dcfa2124d\n\n\u0414\u043b\u044f Debian GNU/Linux:\nhttps://security-tracker.debian.org/tracker/CVE-2025-40186\n\n\u0414\u043b\u044f \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u044b\u0445 \u043f\u0440\u043e\u0434\u0443\u043a\u0442\u043e\u0432 Red Hat Inc.:\nhttps://access.redhat.com/security/cve/cve-2025-40186\n\n\u0414\u043b\u044f \u041e\u0421 \u0410\u043b\u044c\u0442 8 \u0421\u041f: \u0443\u0441\u0442\u0430\u043d\u043e\u0432\u043a\u0430 \u043e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u044f \u0438\u0437 \u043f\u0443\u0431\u043b\u0438\u0447\u043d\u043e\u0433\u043e \u0440\u0435\u043f\u043e\u0437\u0438\u0442\u043e\u0440\u0438\u044f \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u0441\u0440\u0435\u0434\u0441\u0442\u0432\u0430: https://altsp.su/obnovleniya-bezopasnosti/\n\n\u0414\u043b\u044f \u041e\u0421 Astra Linux:\n- \u043e\u0431\u043d\u043e\u0432\u0438\u0442\u044c \u043f\u0430\u043a\u0435\u0442 linux-6.1 \u0434\u043e 6.1.158-1.astra1+ci8 \u0438\u043b\u0438 \u0431\u043e\u043b\u0435\u0435 \u0432\u044b\u0441\u043e\u043a\u043e\u0439 \u0432\u0435\u0440\u0441\u0438\u0438, \u0438\u0441\u043f\u043e\u043b\u044c\u0437\u0443\u044f \u0440\u0435\u043a\u043e\u043c\u0435\u043d\u0434\u0430\u0446\u0438\u0438 \u043f\u0440\u043e\u0438\u0437\u0432\u043e\u0434\u0438\u0442\u0435\u043b\u044f: https://wiki.astralinux.ru/astra-linux-se18-bulletin-2026-0224SE18\n- \u043e\u0431\u043d\u043e\u0432\u0438\u0442\u044c \u043f\u0430\u043a\u0435\u0442 linux-6.12 \u0434\u043e 6.12.60-1.astra1+ci20 \u0438\u043b\u0438 \u0431\u043e\u043b\u0435\u0435 \u0432\u044b\u0441\u043e\u043a\u043e\u0439 \u0432\u0435\u0440\u0441\u0438\u0438, \u0438\u0441\u043f\u043e\u043b\u044c\u0437\u0443\u044f \u0440\u0435\u043a\u043e\u043c\u0435\u043d\u0434\u0430\u0446\u0438\u0438 \u043f\u0440\u043e\u0438\u0437\u0432\u043e\u0434\u0438\u0442\u0435\u043b\u044f: https://wiki.astralinux.ru/astra-linux-se18-bulletin-2026-0224SE18\n\n\u0414\u043b\u044f \u041e\u0421 Astra Linux:\n- \u043e\u0431\u043d\u043e\u0432\u0438\u0442\u044c \u043f\u0430\u043a\u0435\u0442 linux-5.10 \u0434\u043e 5.10.248-1.astra1+ci7 \u0438\u043b\u0438 \u0431\u043e\u043b\u0435\u0435 \u0432\u044b\u0441\u043e\u043a\u043e\u0439 \u0432\u0435\u0440\u0441\u0438\u0438, \u0438\u0441\u043f\u043e\u043b\u044c\u0437\u0443\u044f \u0440\u0435\u043a\u043e\u043c\u0435\u043d\u0434\u0430\u0446\u0438\u0438 \u043f\u0440\u043e\u0438\u0437\u0432\u043e\u0434\u0438\u0442\u0435\u043b\u044f: https://wiki.astralinux.ru/astra-linux-se17-bulletin-2026-0302SE17MD\n- \u043e\u0431\u043d\u043e\u0432\u0438\u0442\u044c \u043f\u0430\u043a\u0435\u0442 linux-6.1 \u0434\u043e 6.1.161-1.astra1 \u0438\u043b\u0438 \u0431\u043e\u043b\u0435\u0435 \u0432\u044b\u0441\u043e\u043a\u043e\u0439 \u0432\u0435\u0440\u0441\u0438\u0438, \u0438\u0441\u043f\u043e\u043b\u044c\u0437\u0443\u044f \u0440\u0435\u043a\u043e\u043c\u0435\u043d\u0434\u0430\u0446\u0438\u0438 \u043f\u0440\u043e\u0438\u0437\u0432\u043e\u0434\u0438\u0442\u0435\u043b\u044f: https://wiki.astralinux.ru/astra-linux-se17-bulletin-2026-0302SE17MD\n\n\u0414\u043b\u044f \u041e\u0421 Astra Linux:\n\u043e\u0431\u043d\u043e\u0432\u0438\u0442\u044c \u043f\u0430\u043a\u0435\u0442 linux-6.1 \u0434\u043e 6.1.158-1.astra1+ci8 \u0438\u043b\u0438 \u0431\u043e\u043b\u0435\u0435 \u0432\u044b\u0441\u043e\u043a\u043e\u0439 \u0432\u0435\u0440\u0441\u0438\u0438, \u0438\u0441\u043f\u043e\u043b\u044c\u0437\u0443\u044f \u0440\u0435\u043a\u043e\u043c\u0435\u043d\u0434\u0430\u0446\u0438\u0438 \u043f\u0440\u043e\u0438\u0437\u0432\u043e\u0434\u0438\u0442\u0435\u043b\u044f: https://wiki.astralinux.ru/astra-linux-se38-bulletin-2026-0305SE38\n\n\u0414\u043b\u044f \u041e\u0421 Astra Linux:\n- \u043e\u0431\u043d\u043e\u0432\u0438\u0442\u044c \u043f\u0430\u043a\u0435\u0442 linux-5.10 \u0434\u043e 5.10.248-1.astra1+ci15 \u0438\u043b\u0438 \u0431\u043e\u043b\u0435\u0435 \u0432\u044b\u0441\u043e\u043a\u043e\u0439 \u0432\u0435\u0440\u0441\u0438\u0438, \u0438\u0441\u043f\u043e\u043b\u044c\u0437\u0443\u044f \u0440\u0435\u043a\u043e\u043c\u0435\u043d\u0434\u0430\u0446\u0438\u0438 \u043f\u0440\u043e\u0438\u0437\u0432\u043e\u0434\u0438\u0442\u0435\u043b\u044f: https://wiki.astralinux.ru/astra-linux-se47-bulletin-2026-0518SE47\n- \u043e\u0431\u043d\u043e\u0432\u0438\u0442\u044c \u043f\u0430\u043a\u0435\u0442 linux-6.1 \u0434\u043e 6.1.161-1.astra1+ci17 \u0438\u043b\u0438 \u0431\u043e\u043b\u0435\u0435 \u0432\u044b\u0441\u043e\u043a\u043e\u0439 \u0432\u0435\u0440\u0441\u0438\u0438, \u0438\u0441\u043f\u043e\u043b\u044c\u0437\u0443\u044f \u0440\u0435\u043a\u043e\u043c\u0435\u043d\u0434\u0430\u0446\u0438\u0438 \u043f\u0440\u043e\u0438\u0437\u0432\u043e\u0434\u0438\u0442\u0435\u043b\u044f: https://wiki.astralinux.ru/astra-linux-se47-bulletin-2026-0518SE47",
  "\u0414\u0430\u0442\u0430 \u0432\u044b\u044f\u0432\u043b\u0435\u043d\u0438\u044f": "01.10.2025",
  "\u0414\u0430\u0442\u0430 \u043f\u043e\u0441\u043b\u0435\u0434\u043d\u0435\u0433\u043e \u043e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u044f": "26.05.2026",
  "\u0414\u0430\u0442\u0430 \u043f\u0443\u0431\u043b\u0438\u043a\u0430\u0446\u0438\u0438": "26.11.2025",
  "\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440": "BDU:2025-14699",
  "\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440\u044b \u0434\u0440\u0443\u0433\u0438\u0445 \u0441\u0438\u0441\u0442\u0435\u043c \u043e\u043f\u0438\u0441\u0430\u043d\u0438\u0439 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "CVE-2025-40186",
  "\u0418\u043d\u0444\u043e\u0440\u043c\u0430\u0446\u0438\u044f \u043e\u0431 \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0438\u0438": "\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0430",
  "\u041a\u043b\u0430\u0441\u0441 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u043a\u043e\u0434\u0430",
  "\u041d\u0430\u0437\u0432\u0430\u043d\u0438\u0435 \u041f\u041e": "Red Hat Enterprise Linux, Debian GNU/Linux, Astra Linux Special Edition (\u0437\u0430\u043f\u0438\u0441\u044c \u0432 \u0435\u0434\u0438\u043d\u043e\u043c \u0440\u0435\u0435\u0441\u0442\u0440\u0435 \u0440\u043e\u0441\u0441\u0438\u0439\u0441\u043a\u0438\u0445 \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c \u2116369), \u0410\u043b\u044c\u0442 8 \u0421\u041f (\u0437\u0430\u043f\u0438\u0441\u044c \u0432 \u0435\u0434\u0438\u043d\u043e\u043c \u0440\u0435\u0435\u0441\u0442\u0440\u0435 \u0440\u043e\u0441\u0441\u0438\u0439\u0441\u043a\u0438\u0445 \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c \u21164305), Linux",
  "\u041d\u0430\u0438\u043c\u0435\u043d\u043e\u0432\u0430\u043d\u0438\u0435 \u041e\u0421 \u0438 \u0442\u0438\u043f \u0430\u043f\u043f\u0430\u0440\u0430\u0442\u043d\u043e\u0439 \u043f\u043b\u0430\u0442\u0444\u043e\u0440\u043c\u044b": "Red Hat, Inc. Red Hat Enterprise Linux 7 , Red Hat, Inc. Red Hat Enterprise Linux 8 , \u0421\u043e\u043e\u0431\u0449\u0435\u0441\u0442\u0432\u043e \u0441\u0432\u043e\u0431\u043e\u0434\u043d\u043e\u0433\u043e \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f Debian GNU/Linux 11 , \u0421\u043e\u043e\u0431\u0449\u0435\u0441\u0442\u0432\u043e \u0441\u0432\u043e\u0431\u043e\u0434\u043d\u043e\u0433\u043e \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f Debian GNU/Linux 12 , \u041e\u041e\u041e \u00ab\u0420\u0443\u0441\u0411\u0418\u0422\u0435\u0445-\u0410\u0441\u0442\u0440\u0430\u00bb Astra Linux Special Edition 1.7  (\u0437\u0430\u043f\u0438\u0441\u044c \u0432 \u0435\u0434\u0438\u043d\u043e\u043c \u0440\u0435\u0435\u0441\u0442\u0440\u0435 \u0440\u043e\u0441\u0441\u0438\u0439\u0441\u043a\u0438\u0445 \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c \u2116369), \u041e\u041e\u041e \u00ab\u0420\u0443\u0441\u0411\u0418\u0422\u0435\u0445-\u0410\u0441\u0442\u0440\u0430\u00bb Astra Linux Special Edition 4.7  (\u0437\u0430\u043f\u0438\u0441\u044c \u0432 \u0435\u0434\u0438\u043d\u043e\u043c \u0440\u0435\u0435\u0441\u0442\u0440\u0435 \u0440\u043e\u0441\u0441\u0438\u0439\u0441\u043a\u0438\u0445 \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c \u2116369), \u0410\u041e \u00ab\u0418\u0412\u041a\u00bb \u0410\u043b\u044c\u0442 8 \u0421\u041f -  (\u0437\u0430\u043f\u0438\u0441\u044c \u0432 \u0435\u0434\u0438\u043d\u043e\u043c \u0440\u0435\u0435\u0441\u0442\u0440\u0435 \u0440\u043e\u0441\u0441\u0438\u0439\u0441\u043a\u0438\u0445 \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c \u21164305), Red Hat, Inc. Red Hat Enterprise Linux 9 , \u041e\u041e\u041e \u00ab\u0420\u0443\u0441\u0411\u0418\u0422\u0435\u0445-\u0410\u0441\u0442\u0440\u0430\u00bb Astra Linux Special Edition 1.8  (\u0437\u0430\u043f\u0438\u0441\u044c \u0432 \u0435\u0434\u0438\u043d\u043e\u043c \u0440\u0435\u0435\u0441\u0442\u0440\u0435 \u0440\u043e\u0441\u0441\u0438\u0439\u0441\u043a\u0438\u0445 \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c \u2116369), Red Hat, Inc. Red Hat Enterprise Linux 10 , \u0421\u043e\u043e\u0431\u0449\u0435\u0441\u0442\u0432\u043e \u0441\u0432\u043e\u0431\u043e\u0434\u043d\u043e\u0433\u043e \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f Debian GNU/Linux 13 , \u0421\u043e\u043e\u0431\u0449\u0435\u0441\u0442\u0432\u043e \u0441\u0432\u043e\u0431\u043e\u0434\u043d\u043e\u0433\u043e \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f Linux \u0434\u043e 6.18 rc1 , \u0421\u043e\u043e\u0431\u0449\u0435\u0441\u0442\u0432\u043e \u0441\u0432\u043e\u0431\u043e\u0434\u043d\u043e\u0433\u043e \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f Linux \u043e\u0442 6.17 \u0434\u043e 6.17.4 , \u0421\u043e\u043e\u0431\u0449\u0435\u0441\u0442\u0432\u043e \u0441\u0432\u043e\u0431\u043e\u0434\u043d\u043e\u0433\u043e \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f Linux \u043e\u0442 5.4.300 \u0434\u043e 5.4.301 , \u0421\u043e\u043e\u0431\u0449\u0435\u0441\u0442\u0432\u043e \u0441\u0432\u043e\u0431\u043e\u0434\u043d\u043e\u0433\u043e \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f Linux \u043e\u0442 5.10.245 \u0434\u043e 5.10.246 , \u0421\u043e\u043e\u0431\u0449\u0435\u0441\u0442\u0432\u043e \u0441\u0432\u043e\u0431\u043e\u0434\u043d\u043e\u0433\u043e \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f Linux \u043e\u0442 5.15.194 \u0434\u043e 5.15.195 , \u0421\u043e\u043e\u0431\u0449\u0435\u0441\u0442\u0432\u043e \u0441\u0432\u043e\u0431\u043e\u0434\u043d\u043e\u0433\u043e \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f Linux \u043e\u0442 6.1.154 \u0434\u043e 6.1.157 , \u0421\u043e\u043e\u0431\u0449\u0435\u0441\u0442\u0432\u043e \u0441\u0432\u043e\u0431\u043e\u0434\u043d\u043e\u0433\u043e \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f Linux \u043e\u0442 6.6.108 \u0434\u043e 6.6.113 , \u0421\u043e\u043e\u0431\u0449\u0435\u0441\u0442\u0432\u043e \u0441\u0432\u043e\u0431\u043e\u0434\u043d\u043e\u0433\u043e \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f Linux \u043e\u0442 6.12.49 \u0434\u043e 6.12.54 , \u0421\u043e\u043e\u0431\u0449\u0435\u0441\u0442\u0432\u043e \u0441\u0432\u043e\u0431\u043e\u0434\u043d\u043e\u0433\u043e \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f Linux 6.16.9 , \u041e\u041e\u041e \u00ab\u0420\u0443\u0441\u0411\u0418\u0422\u0435\u0445-\u0410\u0441\u0442\u0440\u0430\u00bb Astra Linux Special Edition 3.8  (\u0437\u0430\u043f\u0438\u0441\u044c \u0432 \u0435\u0434\u0438\u043d\u043e\u043c \u0440\u0435\u0435\u0441\u0442\u0440\u0435 \u0440\u043e\u0441\u0441\u0438\u0439\u0441\u043a\u0438\u0445 \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c \u2116369)",
  "\u041d\u0430\u0438\u043c\u0435\u043d\u043e\u0432\u0430\u043d\u0438\u0435 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u0444\u0443\u043d\u043a\u0446\u0438\u0438 reqsk_fastopen_remove() \u044f\u0434\u0440\u0430 \u043e\u043f\u0435\u0440\u0430\u0446\u0438\u043e\u043d\u043d\u043e\u0439 \u0441\u0438\u0441\u0442\u0435\u043c\u044b Linux, \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u044e\u0449\u0430\u044f \u043d\u0430\u0440\u0443\u0448\u0438\u0442\u0435\u043b\u044e \u0432\u044b\u0437\u0432\u0430\u0442\u044c \u043e\u0442\u043a\u0430\u0437 \u0432 \u043e\u0431\u0441\u043b\u0443\u0436\u0438\u0432\u0430\u043d\u0438\u0438",
  "\u041d\u0430\u043b\u0438\u0447\u0438\u0435 \u044d\u043a\u0441\u043f\u043b\u043e\u0439\u0442\u0430": "\u0414\u0430\u043d\u043d\u044b\u0435 \u0443\u0442\u043e\u0447\u043d\u044f\u044e\u0442\u0441\u044f",
  "\u041e\u043f\u0438\u0441\u0430\u043d\u0438\u0435 \u043e\u0448\u0438\u0431\u043a\u0438 CWE": "\u0418\u0441\u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u043d\u0438\u0435 \u043f\u043e\u0441\u043b\u0435 \u043e\u0441\u0432\u043e\u0431\u043e\u0436\u0434\u0435\u043d\u0438\u044f (CWE-416), \u041f\u0440\u0435\u0436\u0434\u0435\u0432\u0440\u0435\u043c\u0435\u043d\u043d\u043e\u0435 \u043e\u0441\u0432\u043e\u0431\u043e\u0436\u0434\u0435\u043d\u0438\u0435 \u0440\u0435\u0441\u0443\u0440\u0441\u0430 \u0432 \u0442\u0435\u0447\u0435\u043d\u0438\u0435 \u0441\u0440\u043e\u043a\u0430 \u0435\u0433\u043e \u044d\u043a\u0441\u043f\u043b\u0443\u0430\u0442\u0438\u0440\u043e\u0432\u0430\u043d\u0438\u044f (CWE-826)",
  "\u041e\u043f\u0438\u0441\u0430\u043d\u0438\u0435 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u0444\u0443\u043d\u043a\u0446\u0438\u0438 reqsk_fastopen_remove() \u044f\u0434\u0440\u0430 \u043e\u043f\u0435\u0440\u0430\u0446\u0438\u043e\u043d\u043d\u043e\u0439 \u0441\u0438\u0441\u0442\u0435\u043c\u044b Linux \u0441\u0432\u044f\u0437\u0430\u043d\u0430 \u0441 \u0438\u0441\u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u043d\u0438\u0435\u043c \u043f\u0430\u043c\u044f\u0442\u0438 \u043f\u043e\u0441\u043b\u0435 \u0435\u0435 \u043e\u0441\u0432\u043e\u0431\u043e\u0436\u0434\u0435\u043d\u0438\u044f. \u042d\u043a\u0441\u043f\u043b\u0443\u0430\u0442\u0430\u0446\u0438\u044f \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438 \u043c\u043e\u0436\u0435\u0442 \u043f\u043e\u0437\u0432\u043e\u043b\u0438\u0442\u044c \u043d\u0430\u0440\u0443\u0448\u0438\u0442\u0435\u043b\u044e \u0432\u044b\u0437\u0432\u0430\u0442\u044c \u043e\u0442\u043a\u0430\u0437 \u0432 \u043e\u0431\u0441\u043b\u0443\u0436\u0438\u0432\u0430\u043d\u0438\u0438",
  "\u041f\u043e\u0441\u043b\u0435\u0434\u0441\u0442\u0432\u0438\u044f \u044d\u043a\u0441\u043f\u043b\u0443\u0430\u0442\u0430\u0446\u0438\u0438 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": null,
  "\u041f\u0440\u043e\u0447\u0430\u044f \u0438\u043d\u0444\u043e\u0440\u043c\u0430\u0446\u0438\u044f": null,
  "\u0421\u0432\u044f\u0437\u044c \u0441 \u0438\u043d\u0446\u0438\u0434\u0435\u043d\u0442\u0430\u043c\u0438 \u0418\u0411": "\u0414\u0430\u043d\u043d\u044b\u0435 \u0443\u0442\u043e\u0447\u043d\u044f\u044e\u0442\u0441\u044f",
  "\u0421\u043e\u0441\u0442\u043e\u044f\u043d\u0438\u0435 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u041e\u043f\u0443\u0431\u043b\u0438\u043a\u043e\u0432\u0430\u043d\u0430",
  "\u0421\u043f\u043e\u0441\u043e\u0431 \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0438\u044f": "\u041e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u0435 \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f",
  "\u0421\u043f\u043e\u0441\u043e\u0431 \u044d\u043a\u0441\u043f\u043b\u0443\u0430\u0442\u0430\u0446\u0438\u0438": "\u041c\u0430\u043d\u0438\u043f\u0443\u043b\u0438\u0440\u043e\u0432\u0430\u043d\u0438\u0435 \u0441\u0442\u0440\u0443\u043a\u0442\u0443\u0440\u0430\u043c\u0438 \u0434\u0430\u043d\u043d\u044b\u0445, \u041c\u0430\u043d\u0438\u043f\u0443\u043b\u0438\u0440\u043e\u0432\u0430\u043d\u0438\u0435 \u0440\u0435\u0441\u0443\u0440\u0441\u0430\u043c\u0438",
  "\u0421\u0441\u044b\u043b\u043a\u0438 \u043d\u0430 \u0438\u0441\u0442\u043e\u0447\u043d\u0438\u043a\u0438": "https://lore.kernel.org/linux-cve-announce/2025111244-CVE-2025-40186-b204@gregkh/\nhttps://git.kernel.org/stable/c/2e7cbbbe3d61c63606994b7ff73c72537afe2e1c\t\nhttps://git.kernel.org/stable/c/422c1c173c39bbbae1e0eaaf8aefe40b2596233b\t\nhttps://git.kernel.org/stable/c/643a94b0cf767325e953591c212be2eb826b9d7f\t\nhttps://git.kernel.org/stable/c/64dc47a13aa3d9daf7cec29b44dca8e22a6aea15\t\nhttps://git.kernel.org/stable/c/c11ace909e873118295e9eb22dc8c58b0b50eb32\t\nhttps://git.kernel.org/stable/c/e359b742eac1eac75cff4e38ee2e8cea492acd9b\t\nhttps://git.kernel.org/stable/c/eb85ad5f23268d64b037bfb545cbcba3752f90c7\t\nhttps://git.kernel.org/stable/c/ff6a8883f96a5bc74241ce5b3d431a6dcfa2124d\nhttps://security-tracker.debian.org/tracker/CVE-2025-40186\nhttps://access.redhat.com/security/cve/cve-2025-40186\nhttps://altsp.su/obnovleniya-bezopasnosti/\nhttps://wiki.astralinux.ru/astra-linux-se18-bulletin-2026-0224SE18\nhttps://wiki.astralinux.ru/astra-linux-se17-bulletin-2026-0302SE17MD\nhttps://wiki.astralinux.ru/astra-linux-se38-bulletin-2026-0305SE38\nhttps://wiki.astralinux.ru/astra-linux-se47-bulletin-2026-0518SE47",
  "\u0421\u0442\u0430\u0442\u0443\u0441 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u041f\u043e\u0434\u0442\u0432\u0435\u0440\u0436\u0434\u0435\u043d\u0430 \u043f\u0440\u043e\u0438\u0437\u0432\u043e\u0434\u0438\u0442\u0435\u043b\u0435\u043c",
  "\u0422\u0438\u043f \u041f\u041e": "\u041e\u043f\u0435\u0440\u0430\u0446\u0438\u043e\u043d\u043d\u0430\u044f \u0441\u0438\u0441\u0442\u0435\u043c\u0430",
  "\u0422\u0438\u043f \u043e\u0448\u0438\u0431\u043a\u0438 CWE": "CWE-416, CWE-826",
  "\u0423\u0440\u043e\u0432\u0435\u043d\u044c \u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u0421\u0440\u0435\u0434\u043d\u0438\u0439 \u0443\u0440\u043e\u0432\u0435\u043d\u044c \u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438 (\u0431\u0430\u0437\u043e\u0432\u0430\u044f \u043e\u0446\u0435\u043d\u043a\u0430 CVSS 2.0 \u0441\u043e\u0441\u0442\u0430\u0432\u043b\u044f\u0435\u0442 6)\n\u0412\u044b\u0441\u043e\u043a\u0438\u0439 \u0443\u0440\u043e\u0432\u0435\u043d\u044c \u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438 (\u0431\u0430\u0437\u043e\u0432\u0430\u044f \u043e\u0446\u0435\u043d\u043a\u0430 CVSS 3.1 \u0441\u043e\u0441\u0442\u0430\u0432\u043b\u044f\u0435\u0442 7)"
}

CVE-2025-40186 (GCVE-0-2025-40186)

Vulnerability from cvelistv5 – Published: 2025-11-12 21:56 – Updated: 2026-08-05 12:08

Title

tcp: Don't call reqsk_fastopen_remove() in tcp_conn_request().

Summary

In the Linux kernel, the following vulnerability has been resolved: tcp: Don't call reqsk_fastopen_remove() in tcp_conn_request(). syzbot reported the splat below in tcp_conn_request(). [0] If a listener is close()d while a TFO socket is being processed in tcp_conn_request(), inet_csk_reqsk_queue_add() does not set reqsk->sk and calls inet_child_forget(), which calls tcp_disconnect() for the TFO socket. After the cited commit, tcp_disconnect() calls reqsk_fastopen_remove(), where reqsk_put() is called due to !reqsk->sk. Then, reqsk_fastopen_remove() in tcp_conn_request() decrements the last req->rsk_refcnt and frees reqsk, and __reqsk_free() at the drop_and_free label causes the refcount underflow for the listener and double-free of the reqsk. Let's remove reqsk_fastopen_remove() in tcp_conn_request(). Note that other callers make sure tp->fastopen_rsk is not NULL. [0]: refcount_t: underflow; use-after-free. WARNING: CPU: 12 PID: 5563 at lib/refcount.c:28 refcount_warn_saturate (lib/refcount.c:28) Modules linked in: CPU: 12 UID: 0 PID: 5563 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:refcount_warn_saturate (lib/refcount.c:28) Code: ab e8 8e b4 98 ff 0f 0b c3 cc cc cc cc cc 80 3d a4 e4 d6 01 00 75 9c c6 05 9b e4 d6 01 01 48 c7 c7 e8 df fb ab e8 6a b4 98 ff <0f> 0b e9 03 5b 76 00 cc 80 3d 7d e4 d6 01 00 0f 85 74 ff ff ff c6 RSP: 0018:ffffa79fc0304a98 EFLAGS: 00010246 RAX: d83af4db1c6b3900 RBX: ffff9f65c7a69020 RCX: d83af4db1c6b3900 RDX: 0000000000000000 RSI: 00000000ffff7fff RDI: ffffffffac78a280 RBP: 000000009d781b60 R08: 0000000000007fff R09: ffffffffac6ca280 R10: 0000000000017ffd R11: 0000000000000004 R12: ffff9f65c7b4f100 R13: ffff9f65c7d23c00 R14: ffff9f65c7d26000 R15: ffff9f65c7a64ef8 FS: 00007f9f962176c0(0000) GS:ffff9f65fcf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000000180 CR3: 000000000dbbe006 CR4: 0000000000372ef0 Call Trace: <IRQ> tcp_conn_request (./include/linux/refcount.h:400 ./include/linux/refcount.h:432 ./include/linux/refcount.h:450 ./include/net/sock.h:1965 ./include/net/request_sock.h:131 net/ipv4/tcp_input.c:7301) tcp_rcv_state_process (net/ipv4/tcp_input.c:6708) tcp_v6_do_rcv (net/ipv6/tcp_ipv6.c:1670) tcp_v6_rcv (net/ipv6/tcp_ipv6.c:1906) ip6_protocol_deliver_rcu (net/ipv6/ip6_input.c:438) ip6_input (net/ipv6/ip6_input.c:500) ipv6_rcv (net/ipv6/ip6_input.c:311) __netif_receive_skb (net/core/dev.c:6104) process_backlog (net/core/dev.c:6456) __napi_poll (net/core/dev.c:7506) net_rx_action (net/core/dev.c:7569 net/core/dev.c:7696) handle_softirqs (kernel/softirq.c:579) do_softirq (kernel/softirq.c:480) </IRQ>

Severity

8.1 (High)


                        
                          CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Assigner

Linux mitre root

References

8 references

URL	Tags
https://git.kernel.org/stable/c/e359b742eac1eac75…
https://git.kernel.org/stable/c/ff6a8883f96a5bc74…
https://git.kernel.org/stable/c/eb85ad5f23268d64b…
https://git.kernel.org/stable/c/643a94b0cf767325e…
https://git.kernel.org/stable/c/422c1c173c39bbbae…
https://git.kernel.org/stable/c/c11ace909e8731182…
https://git.kernel.org/stable/c/64dc47a13aa3d9daf…
https://git.kernel.org/stable/c/2e7cbbbe3d61c6360…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 7ec092a91ff351dcde89c23e795b73a328274db6 , < e359b742eac1eac75cff4e38ee2e8cea492acd9b (git) Affected: a4378dedd6e07e62f2fccb17d78c9665718763d0 , < ff6a8883f96a5bc74241ce5b3d431a6dcfa2124d (git) Affected: 33a4fdf0b4a25f8ce65380c3b0136b407ca57609 , < eb85ad5f23268d64b037bfb545cbcba3752f90c7 (git) Affected: 17d699727577814198d744d6afe54735c6b54c99 , < 643a94b0cf767325e953591c212be2eb826b9d7f (git) Affected: dfd06131107e7b699ef1e2a24ed2f7d17c917753 , < 422c1c173c39bbbae1e0eaaf8aefe40b2596233b (git) Affected: fa4749c065644af4db496b338452a69a3e5147d9 , < c11ace909e873118295e9eb22dc8c58b0b50eb32 (git) Affected: 45c8a6cc2bcd780e634a6ba8e46bffbdf1fc5c01 , < 64dc47a13aa3d9daf7cec29b44dca8e22a6aea15 (git) Affected: 45c8a6cc2bcd780e634a6ba8e46bffbdf1fc5c01 , < 2e7cbbbe3d61c63606994b7ff73c72537afe2e1c (git) Affected: ae313d14b45eca7a6bb29cb9bf396d977e7d28fb (git) Affected: 5.4.300 , < 5.4.301 (semver) Affected: 5.10.245 , < 5.10.246 (semver) Affected: 5.15.194 , < 5.15.195 (semver) Affected: 6.1.154 , < 6.1.157 (semver) Affected: 6.6.108 , < 6.6.113 (semver) Affected: 6.12.49 , < 6.12.54 (semver) Affected: 6.16.9 , < 6.17 (semver)
Linux	Linux	Affected: 6.17 Unaffected: 0 , < 6.17 (semver) Unaffected: 5.4.301 , ≤ 5.4.* (semver) Unaffected: 5.10.246 , ≤ 5.10.* (semver) Unaffected: 5.15.195 , ≤ 5.15.* (semver) Unaffected: 6.1.157 , ≤ 6.1.* (semver) Unaffected: 6.6.113 , ≤ 6.6.* (semver) Unaffected: 6.12.54 , ≤ 6.12.* (semver) Unaffected: 6.17.4 , ≤ 6.17.* (semver) Unaffected: 6.18 , ≤ * (original_commit_for_fix)

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{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/ipv4/tcp_input.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "e359b742eac1eac75cff4e38ee2e8cea492acd9b",
              "status": "affected",
              "version": "7ec092a91ff351dcde89c23e795b73a328274db6",
              "versionType": "git"
            },
            {
              "lessThan": "ff6a8883f96a5bc74241ce5b3d431a6dcfa2124d",
              "status": "affected",
              "version": "a4378dedd6e07e62f2fccb17d78c9665718763d0",
              "versionType": "git"
            },
            {
              "lessThan": "eb85ad5f23268d64b037bfb545cbcba3752f90c7",
              "status": "affected",
              "version": "33a4fdf0b4a25f8ce65380c3b0136b407ca57609",
              "versionType": "git"
            },
            {
              "lessThan": "643a94b0cf767325e953591c212be2eb826b9d7f",
              "status": "affected",
              "version": "17d699727577814198d744d6afe54735c6b54c99",
              "versionType": "git"
            },
            {
              "lessThan": "422c1c173c39bbbae1e0eaaf8aefe40b2596233b",
              "status": "affected",
              "version": "dfd06131107e7b699ef1e2a24ed2f7d17c917753",
              "versionType": "git"
            },
            {
              "lessThan": "c11ace909e873118295e9eb22dc8c58b0b50eb32",
              "status": "affected",
              "version": "fa4749c065644af4db496b338452a69a3e5147d9",
              "versionType": "git"
            },
            {
              "lessThan": "64dc47a13aa3d9daf7cec29b44dca8e22a6aea15",
              "status": "affected",
              "version": "45c8a6cc2bcd780e634a6ba8e46bffbdf1fc5c01",
              "versionType": "git"
            },
            {
              "lessThan": "2e7cbbbe3d61c63606994b7ff73c72537afe2e1c",
              "status": "affected",
              "version": "45c8a6cc2bcd780e634a6ba8e46bffbdf1fc5c01",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "ae313d14b45eca7a6bb29cb9bf396d977e7d28fb",
              "versionType": "git"
            },
            {
              "lessThan": "5.4.301",
              "status": "affected",
              "version": "5.4.300",
              "versionType": "semver"
            },
            {
              "lessThan": "5.10.246",
              "status": "affected",
              "version": "5.10.245",
              "versionType": "semver"
            },
            {
              "lessThan": "5.15.195",
              "status": "affected",
              "version": "5.15.194",
              "versionType": "semver"
            },
            {
              "lessThan": "6.1.157",
              "status": "affected",
              "version": "6.1.154",
              "versionType": "semver"
            },
            {
              "lessThan": "6.6.113",
              "status": "affected",
              "version": "6.6.108",
              "versionType": "semver"
            },
            {
              "lessThan": "6.12.54",
              "status": "affected",
              "version": "6.12.49",
              "versionType": "semver"
            },
            {
              "lessThan": "6.17",
              "status": "affected",
              "version": "6.16.9",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/ipv4/tcp_input.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.17"
            },
            {
              "lessThan": "6.17",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.4.*",
              "status": "unaffected",
              "version": "5.4.301",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.246",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.195",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.157",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.113",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.54",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.17.*",
              "status": "unaffected",
              "version": "6.17.4",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.18",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.4.301",
                  "versionStartIncluding": "5.4.300",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.10.246",
                  "versionStartIncluding": "5.10.245",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.15.195",
                  "versionStartIncluding": "5.15.194",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.1.157",
                  "versionStartIncluding": "6.1.154",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.113",
                  "versionStartIncluding": "6.6.108",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.54",
                  "versionStartIncluding": "6.12.49",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.17.4",
                  "versionStartIncluding": "6.17",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18",
                  "versionStartIncluding": "6.17",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionStartIncluding": "6.16.9",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ntcp: Don\u0027t call reqsk_fastopen_remove() in tcp_conn_request().\n\nsyzbot reported the splat below in tcp_conn_request(). [0]\n\nIf a listener is close()d while a TFO socket is being processed in\ntcp_conn_request(), inet_csk_reqsk_queue_add() does not set reqsk-\u003esk\nand calls inet_child_forget(), which calls tcp_disconnect() for the\nTFO socket.\n\nAfter the cited commit, tcp_disconnect() calls reqsk_fastopen_remove(),\nwhere reqsk_put() is called due to !reqsk-\u003esk.\n\nThen, reqsk_fastopen_remove() in tcp_conn_request() decrements the\nlast req-\u003ersk_refcnt and frees reqsk, and __reqsk_free() at the\ndrop_and_free label causes the refcount underflow for the listener\nand double-free of the reqsk.\n\nLet\u0027s remove reqsk_fastopen_remove() in tcp_conn_request().\n\nNote that other callers make sure tp-\u003efastopen_rsk is not NULL.\n\n[0]:\nrefcount_t: underflow; use-after-free.\nWARNING: CPU: 12 PID: 5563 at lib/refcount.c:28 refcount_warn_saturate (lib/refcount.c:28)\nModules linked in:\nCPU: 12 UID: 0 PID: 5563 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full)\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025\nRIP: 0010:refcount_warn_saturate (lib/refcount.c:28)\nCode: ab e8 8e b4 98 ff 0f 0b c3 cc cc cc cc cc 80 3d a4 e4 d6 01 00 75 9c c6 05 9b e4 d6 01 01 48 c7 c7 e8 df fb ab e8 6a b4 98 ff \u003c0f\u003e 0b e9 03 5b 76 00 cc 80 3d 7d e4 d6 01 00 0f 85 74 ff ff ff c6\nRSP: 0018:ffffa79fc0304a98 EFLAGS: 00010246\nRAX: d83af4db1c6b3900 RBX: ffff9f65c7a69020 RCX: d83af4db1c6b3900\nRDX: 0000000000000000 RSI: 00000000ffff7fff RDI: ffffffffac78a280\nRBP: 000000009d781b60 R08: 0000000000007fff R09: ffffffffac6ca280\nR10: 0000000000017ffd R11: 0000000000000004 R12: ffff9f65c7b4f100\nR13: ffff9f65c7d23c00 R14: ffff9f65c7d26000 R15: ffff9f65c7a64ef8\nFS:  00007f9f962176c0(0000) GS:ffff9f65fcf00000(0000) knlGS:0000000000000000\nCS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\nCR2: 0000200000000180 CR3: 000000000dbbe006 CR4: 0000000000372ef0\nCall Trace:\n \u003cIRQ\u003e\n tcp_conn_request (./include/linux/refcount.h:400 ./include/linux/refcount.h:432 ./include/linux/refcount.h:450 ./include/net/sock.h:1965 ./include/net/request_sock.h:131 net/ipv4/tcp_input.c:7301)\n tcp_rcv_state_process (net/ipv4/tcp_input.c:6708)\n tcp_v6_do_rcv (net/ipv6/tcp_ipv6.c:1670)\n tcp_v6_rcv (net/ipv6/tcp_ipv6.c:1906)\n ip6_protocol_deliver_rcu (net/ipv6/ip6_input.c:438)\n ip6_input (net/ipv6/ip6_input.c:500)\n ipv6_rcv (net/ipv6/ip6_input.c:311)\n __netif_receive_skb (net/core/dev.c:6104)\n process_backlog (net/core/dev.c:6456)\n __napi_poll (net/core/dev.c:7506)\n net_rx_action (net/core/dev.c:7569 net/core/dev.c:7696)\n handle_softirqs (kernel/softirq.c:579)\n do_softirq (kernel/softirq.c:480)\n \u003c/IRQ\u003e"
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 8.1,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:N - The vulnerable code is in the TCP/IP stack\u0027s inbound SYN-processing path (tcp_v6_rcv \u2192 tcp_rcv_state_process \u2192 tcp_conn_request), triggered by a received TCP Fast Open SYN packet from a remote peer.\nAC:H - Triggering requires the listener socket to transition out of TCP_LISTEN (a local close()/shutdown()) at the exact moment an inbound TFO SYN is being processed; a remote attacker cannot control the timing of that close, so success depends on conditions beyond their control.\nPR:N - The TFO SYN is processed pre-connection with no authentication; an unauthenticated remote attacker needs no privileges to reach tcp_conn_request().\nUI:N - The bug is triggered purely by network packet processing racing with a listener close; no victim interaction is required.\nS:U - The corruption stays within the kernel\u0027s own memory/security authority (request_sock slab and listener refcount); no VM/IOMMU/sandbox boundary is crossed.\nC:H - The refcount underflow yields a use-after-free/double-free of a request_sock, giving an attacker control over freed-object contents that can be leveraged to read adjacent kernel memory.\nI:H - The double-free/UAF is a heap-corruption primitive that can be groomed into an arbitrary-write / control-flow-hijack, so integrity impact is high.\nA:H - The refcount underflow and double-free reliably corrupt kernel memory and crash the kernel (oops/panic in softirq context), a high availability impact."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T12:08:24.563Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/e359b742eac1eac75cff4e38ee2e8cea492acd9b"
        },
        {
          "url": "https://git.kernel.org/stable/c/ff6a8883f96a5bc74241ce5b3d431a6dcfa2124d"
        },
        {
          "url": "https://git.kernel.org/stable/c/eb85ad5f23268d64b037bfb545cbcba3752f90c7"
        },
        {
          "url": "https://git.kernel.org/stable/c/643a94b0cf767325e953591c212be2eb826b9d7f"
        },
        {
          "url": "https://git.kernel.org/stable/c/422c1c173c39bbbae1e0eaaf8aefe40b2596233b"
        },
        {
          "url": "https://git.kernel.org/stable/c/c11ace909e873118295e9eb22dc8c58b0b50eb32"
        },
        {
          "url": "https://git.kernel.org/stable/c/64dc47a13aa3d9daf7cec29b44dca8e22a6aea15"
        },
        {
          "url": "https://git.kernel.org/stable/c/2e7cbbbe3d61c63606994b7ff73c72537afe2e1c"
        }
      ],
      "title": "tcp: Don\u0027t call reqsk_fastopen_remove() in tcp_conn_request().",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2025-40186",
    "datePublished": "2025-11-12T21:56:29.033Z",
    "dateReserved": "2025-04-16T07:20:57.177Z",
    "dateUpdated": "2026-08-05T12:08:24.563Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.