Vulnerability-Lookup

BDU:2026-10731 (CVE-2026-31669)

Vulnerability from fstec – Published: 2026-07-30 – Updated: 2026-08-19 – View on bdu.fstec.ru Fixed

Title

Уязвимость функции mptcp_subflow_init() модуля net/mptcp/protocol.c ядра операционной системы Linux, позволяющая нарушителю оказать воздействие на конфиденциальность, целостность и доступность защищаемой информации

Summary

Уязвимость функции mptcp_subflow_init() модуля net/mptcp/protocol.c ядра операционной системы Linux связана с повторным использованием ранее освобожденной памяти Эксплуатация уязвимости может позволить нарушителю оказать воздействие на конфиденциальность, целостность и доступность защищаемой информации

Severity

10.0 (High) CVSS 2.0


                      
                        AV:N/AC:L/Au:N/C:C/I:C/A:C

9.8 (Critical) CVSS 3.1


                      
                        CVSS:3.1/AV:N/AC:L/PR:N/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-763 - Освобождение неверного указателя или ссылки

Aliases

CVE-2026-31669

References

12 references

URL
https://git.kernel.org/stable/c/fb1f54b7d16f393b8b65d328410f78b4beea8fcc
https://git.kernel.org/stable/c/f6e1f25fa5e733570f6d6fe37a4dfed2a0deba47
https://git.kernel.org/stable/c/3fd6547f5b8ac99687be6d937a0321efda760597
https://git.kernel.org/stable/c/b313e9037d98c13938740e5ebda7852929366dff
https://git.kernel.org/stable/c/eb9c6aeb512f877cf397deb1e4526f646c70e4a7
https://git.kernel.org/stable/c/15fa9ead4d5e6b6b9c794e84144146c917f2cb62
https://www.cve.org/CVERecord?id=CVE-2026-31669
https://git.kernel.org/linus/9b55b253907e7431210483519c5ad711a37dafa1
https://lore.kernel.org/linux-cve-announce/2026042406-CVE-2026-31669-0e0d@gregkh/
https://security-tracker.debian.org/tracker/CVE-2026-31669
https://access.redhat.com/security/cve/cve-2026-31669
https://altsp.su/obnovleniya-bezopasnosti/

Impacted products

4 products from 4 vendors

Vendors

Red Hat, Inc., Сообщество свободного программного обеспечения, АО «ИВК»

Products

Red Hat Enterprise Linux, Debian GNU/Linux, АЛЬТ СП 10, Linux

Versions

8 (Red Hat Enterprise Linux), 11 (Debian GNU/Linux), 12 (Debian GNU/Linux), 9 (Red Hat Enterprise Linux), 8.4 Advanced Mission Critical Update Support (Red Hat Enterprise Linux), - (АЛЬТ СП 10), 8.6 Advanced Mission Critical Update Support (Red Hat Enterprise Linux), 10 (Red Hat Enterprise Linux), 8.8 Telecommunications Update Service (Red Hat Enterprise Linux), 8.8 Update Services for SAP Solutions (Red Hat Enterprise Linux), 9.2 Update Services for SAP Solutions (Red Hat Enterprise Linux), 13 (Debian GNU/Linux), 8.6 Extended Update Support Long-Life Add-On (Red Hat Enterprise Linux), 8.4 Extended Update Support Long-Life Add-On (Red Hat Enterprise Linux), 9.6 Extended Update Support (Red Hat Enterprise Linux), 10.0 Extended Update Support (Red Hat Enterprise Linux), 9.4 Update Services for SAP Solutions (Red Hat Enterprise Linux), от 5.16 до 6.1.168 включительно (Linux), от 6.2 до 6.6.134 включительно (Linux), от 6.7 до 6.12.81 включительно (Linux), от 6.13 до 6.18.22 включительно (Linux), от 6.19 до 6.19.12 включительно (Linux), от 5.12 до 5.15.202 включительно (Linux)

Product types

Operating system

Platforms

Red Hat, Inc. Red Hat Enterprise Linux 8, Сообщество свободного программного обеспечения Debian GNU/Linux 11, Сообщество свободного программного обеспечения Debian GNU/Linux 12, Inc. Red Hat Enterprise Linux 9, Inc. Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support, АО «ИВК» АЛЬТ СП 10 -, Inc. Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support, Inc. Red Hat Enterprise Linux 10, Inc. Red Hat Enterprise Linux 8.8 Telecommunications Update Service, Inc. Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions, Inc. Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions, Сообщество свободного программного обеспечения Debian GNU/Linux 13, Inc. Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On, Inc. Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On, Inc. Red Hat Enterprise Linux 9.6 Extended Update Support, Inc. Red Hat Enterprise Linux 10.0 Extended Update Support, Inc. Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions, Сообщество свободного программного обеспечения Linux от 5.16 до 6.1.168 включительно, Сообщество свободного программного обеспечения Linux от 6.2 до 6.6.134 включительно, Сообщество свободного программного обеспечения Linux от 6.7 до 6.12.81 включительно, Сообщество свободного программного обеспечения Linux от 6.13 до 6.18.22 включительно, Сообщество свободного программного обеспечения Linux от 6.19 до 6.19.12 включительно, Сообщество свободного программного обеспечения Linux от 5.12 до 5.15.202 включительно

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/2026042406-CVE-2026-31669-0e0d@gregkh/ https://git.kernel.org/stable/c/fb1f54b7d16f393b8b65d328410f78b4beea8fcc https://git.kernel.org/stable/c/f6e1f25fa5e733570f6d6fe37a4dfed2a0deba47 https://git.kernel.org/stable/c/3fd6547f5b8ac99687be6d937a0321efda760597 https://git.kernel.org/stable/c/b313e9037d98c13938740e5ebda7852929366dff https://git.kernel.org/stable/c/eb9c6aeb512f877cf397deb1e4526f646c70e4a7 https://git.kernel.org/stable/c/15fa9ead4d5e6b6b9c794e84144146c917f2cb62 https://git.kernel.org/linus/9b55b253907e7431210483519c5ad711a37dafa1 Для Debian GNU/Linux: https://security-tracker.debian.org/tracker/CVE-2026-31669 Для продуктов Red Hat Inc.: https://access.redhat.com/security/cve/cve-2026-31669 Для ОС АЛЬТ СП 10: установка обновления из публичного репозитория программного средства: https://altsp.su/obnovleniya-bezopasnosti/

JSON

To clipboard

{
  "CVSS 2.0": "AV:N/AC:L/Au:N/C:C/I:C/A:C",
  "CVSS 3.0": "AV:N/AC:L/PR:N/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, \u0410\u041e \u00ab\u0418\u0412\u041a\u00bb",
  "\u0412\u0435\u0440\u0441\u0438\u044f \u041f\u041e": "8 (Red Hat Enterprise Linux), 11 (Debian GNU/Linux), 12 (Debian GNU/Linux), 9 (Red Hat Enterprise Linux), 8.4 Advanced Mission Critical Update Support (Red Hat Enterprise Linux), - (\u0410\u041b\u042c\u0422 \u0421\u041f 10), 8.6 Advanced Mission Critical Update Support (Red Hat Enterprise Linux), 10 (Red Hat Enterprise Linux), 8.8 Telecommunications Update Service (Red Hat Enterprise Linux), 8.8 Update Services for SAP Solutions (Red Hat Enterprise Linux), 9.2 Update Services for SAP Solutions (Red Hat Enterprise Linux), 13 (Debian GNU/Linux), 8.6 Extended Update Support Long-Life Add-On (Red Hat Enterprise Linux), 8.4 Extended Update Support Long-Life Add-On (Red Hat Enterprise Linux), 9.6 Extended Update Support (Red Hat Enterprise Linux), 10.0 Extended Update Support (Red Hat Enterprise Linux), 9.4 Update Services for SAP Solutions (Red Hat Enterprise Linux), \u043e\u0442 5.16 \u0434\u043e 6.1.168 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e (Linux), \u043e\u0442 6.2 \u0434\u043e 6.6.134 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e (Linux), \u043e\u0442 6.7 \u0434\u043e 6.12.81 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e (Linux), \u043e\u0442 6.13 \u0434\u043e 6.18.22 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e (Linux), \u043e\u0442 6.19 \u0434\u043e 6.19.12 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e (Linux), \u043e\u0442 5.12 \u0434\u043e 5.15.202 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e (Linux)",
  "\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\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\n\u0414\u043b\u044f Linux:\nhttps://lore.kernel.org/linux-cve-announce/2026042406-CVE-2026-31669-0e0d@gregkh/\nhttps://git.kernel.org/stable/c/fb1f54b7d16f393b8b65d328410f78b4beea8fcc\nhttps://git.kernel.org/stable/c/f6e1f25fa5e733570f6d6fe37a4dfed2a0deba47\nhttps://git.kernel.org/stable/c/3fd6547f5b8ac99687be6d937a0321efda760597\nhttps://git.kernel.org/stable/c/b313e9037d98c13938740e5ebda7852929366dff\nhttps://git.kernel.org/stable/c/eb9c6aeb512f877cf397deb1e4526f646c70e4a7\nhttps://git.kernel.org/stable/c/15fa9ead4d5e6b6b9c794e84144146c917f2cb62\nhttps://git.kernel.org/linus/9b55b253907e7431210483519c5ad711a37dafa1\n\n\u0414\u043b\u044f Debian GNU/Linux:\nhttps://security-tracker.debian.org/tracker/CVE-2026-31669\n\n\u0414\u043b\u044f \u043f\u0440\u043e\u0434\u0443\u043a\u0442\u043e\u0432 Red Hat Inc.:\nhttps://access.redhat.com/security/cve/cve-2026-31669\n\n\u0414\u043b\u044f \u041e\u0421 \u0410\u041b\u042c\u0422 \u0421\u041f 10: \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/",
  "\u0414\u0430\u0442\u0430 \u0432\u044b\u044f\u0432\u043b\u0435\u043d\u0438\u044f": "06.04.2026",
  "\u0414\u0430\u0442\u0430 \u043f\u043e\u0441\u043b\u0435\u0434\u043d\u0435\u0433\u043e \u043e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u044f": "19.08.2026",
  "\u0414\u0430\u0442\u0430 \u043f\u0443\u0431\u043b\u0438\u043a\u0430\u0446\u0438\u0438": "30.07.2026",
  "\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440": "BDU:2026-10731",
  "\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-2026-31669",
  "\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, \u0410\u041b\u042c\u0422 \u0421\u041f 10, 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 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 , Red Hat, Inc. Red Hat Enterprise Linux 9 , Red Hat, Inc. Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support , \u0410\u041e \u00ab\u0418\u0412\u041a\u00bb \u0410\u041b\u042c\u0422 \u0421\u041f 10 - , Red Hat, Inc. Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support , Red Hat, Inc. Red Hat Enterprise Linux 10 , Red Hat, Inc. Red Hat Enterprise Linux 8.8 Telecommunications Update Service , Red Hat, Inc. Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions , Red Hat, Inc. Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions , \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 , Red Hat, Inc. Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On , Red Hat, Inc. Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On , Red Hat, Inc. Red Hat Enterprise Linux 9.6 Extended Update Support , Red Hat, Inc. Red Hat Enterprise Linux 10.0 Extended Update Support , Red Hat, Inc. Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions , \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 5.16 \u0434\u043e 6.1.168 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e , \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 6.2 \u0434\u043e 6.6.134 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e , \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 6.7 \u0434\u043e 6.12.81 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e , \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 6.13 \u0434\u043e 6.18.22 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e , \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 6.19 \u0434\u043e 6.19.12 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e , \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 5.12 \u0434\u043e 5.15.202 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e ",
  "\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 mptcp_subflow_init() \u043c\u043e\u0434\u0443\u043b\u044f net/mptcp/protocol.c \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 \u043e\u043a\u0430\u0437\u0430\u0442\u044c \u0432\u043e\u0437\u0434\u0435\u0439\u0441\u0442\u0432\u0438\u0435 \u043d\u0430 \u043a\u043e\u043d\u0444\u0438\u0434\u0435\u043d\u0446\u0438\u0430\u043b\u044c\u043d\u043e\u0441\u0442\u044c, \u0446\u0435\u043b\u043e\u0441\u0442\u043d\u043e\u0441\u0442\u044c \u0438 \u0434\u043e\u0441\u0442\u0443\u043f\u043d\u043e\u0441\u0442\u044c \u0437\u0430\u0449\u0438\u0449\u0430\u0435\u043c\u043e\u0439 \u0438\u043d\u0444\u043e\u0440\u043c\u0430\u0446\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), \u041e\u0441\u0432\u043e\u0431\u043e\u0436\u0434\u0435\u043d\u0438\u0435 \u043d\u0435\u0432\u0435\u0440\u043d\u043e\u0433\u043e \u0443\u043a\u0430\u0437\u0430\u0442\u0435\u043b\u044f \u0438\u043b\u0438 \u0441\u0441\u044b\u043b\u043a\u0438 (CWE-763)",
  "\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 mptcp_subflow_init() \u043c\u043e\u0434\u0443\u043b\u044f net/mptcp/protocol.c \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 \u043f\u043e\u0432\u0442\u043e\u0440\u043d\u044b\u043c \u0438\u0441\u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u043d\u0438\u0435\u043c \u0440\u0430\u043d\u0435\u0435 \u043e\u0441\u0432\u043e\u0431\u043e\u0436\u0434\u0435\u043d\u043d\u043e\u0439 \u043f\u0430\u043c\u044f\u0442\u0438 \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 \u043e\u043a\u0430\u0437\u0430\u0442\u044c \u0432\u043e\u0437\u0434\u0435\u0439\u0441\u0442\u0432\u0438\u0435 \u043d\u0430 \u043a\u043e\u043d\u0444\u0438\u0434\u0435\u043d\u0446\u0438\u0430\u043b\u044c\u043d\u043e\u0441\u0442\u044c, \u0446\u0435\u043b\u043e\u0441\u0442\u043d\u043e\u0441\u0442\u044c \u0438 \u0434\u043e\u0441\u0442\u0443\u043f\u043d\u043e\u0441\u0442\u044c \u0437\u0430\u0449\u0438\u0449\u0430\u0435\u043c\u043e\u0439 \u0438\u043d\u0444\u043e\u0440\u043c\u0430\u0446\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://git.kernel.org/stable/c/fb1f54b7d16f393b8b65d328410f78b4beea8fcc\nhttps://git.kernel.org/stable/c/f6e1f25fa5e733570f6d6fe37a4dfed2a0deba47\nhttps://git.kernel.org/stable/c/3fd6547f5b8ac99687be6d937a0321efda760597\nhttps://git.kernel.org/stable/c/b313e9037d98c13938740e5ebda7852929366dff\nhttps://git.kernel.org/stable/c/eb9c6aeb512f877cf397deb1e4526f646c70e4a7\nhttps://git.kernel.org/stable/c/15fa9ead4d5e6b6b9c794e84144146c917f2cb62\nhttps://www.cve.org/CVERecord?id=CVE-2026-31669\nhttps://git.kernel.org/linus/9b55b253907e7431210483519c5ad711a37dafa1\nhttps://lore.kernel.org/linux-cve-announce/2026042406-CVE-2026-31669-0e0d@gregkh/\nhttps://security-tracker.debian.org/tracker/CVE-2026-31669\nhttps://access.redhat.com/security/cve/cve-2026-31669\nhttps://altsp.su/obnovleniya-bezopasnosti/",
  "\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-763",
  "\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": "\u041a\u0440\u0438\u0442\u0438\u0447\u0435\u0441\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 2.0 \u0441\u043e\u0441\u0442\u0430\u0432\u043b\u044f\u0435\u0442 10)\n\u041a\u0440\u0438\u0442\u0438\u0447\u0435\u0441\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 9,8)"
}

CVE-2026-31669 (GCVE-0-2026-31669)

Vulnerability from cvelistv5 – Published: 2026-04-24 14:45 – Updated: 2026-09-08 08:47

Title

mptcp: fix slab-use-after-free in __inet_lookup_established

Summary

In the Linux kernel, the following vulnerability has been resolved: mptcp: fix slab-use-after-free in __inet_lookup_established The ehash table lookups are lockless and rely on SLAB_TYPESAFE_BY_RCU to guarantee socket memory stability during RCU read-side critical sections. Both tcp_prot and tcpv6_prot have their slab caches created with this flag via proto_register(). However, MPTCP's mptcp_subflow_init() copies tcpv6_prot into tcpv6_prot_override during inet_init() (fs_initcall, level 5), before inet6_init() (module_init/device_initcall, level 6) has called proto_register(&tcpv6_prot). At that point, tcpv6_prot.slab is still NULL, so tcpv6_prot_override.slab remains NULL permanently. This causes MPTCP v6 subflow child sockets to be allocated via kmalloc (falling into kmalloc-4k) instead of the TCPv6 slab cache. The kmalloc-4k cache lacks SLAB_TYPESAFE_BY_RCU, so when these sockets are freed without SOCK_RCU_FREE (which is cleared for child sockets by design), the memory can be immediately reused. Concurrent ehash lookups under rcu_read_lock can then access freed memory, triggering a slab-use-after-free in __inet_lookup_established. Fix this by splitting the IPv6-specific initialization out of mptcp_subflow_init() into a new mptcp_subflow_v6_init(), called from mptcp_proto_v6_init() before protocol registration. This ensures tcpv6_prot_override.slab correctly inherits the SLAB_TYPESAFE_BY_RCU slab cache.

Severity

9.8 (Critical)


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

Assigner

Linux mitre root

References

9 references

URL	Tags
https://git.kernel.org/stable/c/f6e1f25fa5e733570…
https://git.kernel.org/stable/c/fb1f54b7d16f393b8…
https://git.kernel.org/stable/c/3fd6547f5b8ac9968…
https://git.kernel.org/stable/c/eb9c6aeb512f877cf…
https://git.kernel.org/stable/c/15fa9ead4d5e6b6b9…
https://git.kernel.org/stable/c/b313e9037d98c1393…
https://git.kernel.org/stable/c/9b55b253907e74312…
https://cert-portal.siemens.com/productcert/html/…
https://cert-portal.siemens.com/productcert/html/…

Impacted products

8 products

Vendor	Product	Version
Linux	Linux	Affected: b19bc2945b40b9fd38e835700907ffe8534ef0de , < f6e1f25fa5e733570f6d6fe37a4dfed2a0deba47 (git) Affected: b19bc2945b40b9fd38e835700907ffe8534ef0de , < fb1f54b7d16f393b8b65d328410f78b4beea8fcc (git) Affected: b19bc2945b40b9fd38e835700907ffe8534ef0de , < 3fd6547f5b8ac99687be6d937a0321efda760597 (git) Affected: b19bc2945b40b9fd38e835700907ffe8534ef0de , < eb9c6aeb512f877cf397deb1e4526f646c70e4a7 (git) Affected: b19bc2945b40b9fd38e835700907ffe8534ef0de , < 15fa9ead4d5e6b6b9c794e84144146c917f2cb62 (git) Affected: b19bc2945b40b9fd38e835700907ffe8534ef0de , < b313e9037d98c13938740e5ebda7852929366dff (git) Affected: b19bc2945b40b9fd38e835700907ffe8534ef0de , < 9b55b253907e7431210483519c5ad711a37dafa1 (git)
Linux	Linux	Affected: 5.12 Unaffected: 0 , < 5.12 (semver) Unaffected: 5.15.203 , ≤ 5.15.* (semver) Unaffected: 6.1.169 , ≤ 6.1.* (semver) Unaffected: 6.6.135 , ≤ 6.6.* (semver) Unaffected: 6.12.82 , ≤ 6.12.* (semver) Unaffected: 6.18.23 , ≤ 6.18.* (semver) Unaffected: 6.19.13 , ≤ 6.19.* (semver) Unaffected: 7.0 , ≤ * (original_commit_for_fix)
Siemens	SIMATIC S7-1500 CPU 1518-4 PN/DP MFP	Affected: V3.1.6 , < * (custom)
Siemens	SIMATIC S7-1500 CPU 1518-4 PN/DP MFP	Affected: V3.1.5 , < * (custom)
Siemens	SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP	Affected: V3.1.6 , < * (custom)
Siemens	SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP	Affected: V3.1.5 , < * (custom)
Siemens	SIPLUS S7-1500 CPU 1518-4 PN/DP MFP	Affected: V3.1.6 , < * (custom)
Siemens	SIPLUS S7-1500 CPU 1518-4 PN/DP MFP	Affected: V3.1.5 , < * (custom)

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{
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          {
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            "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP",
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            "versions": [
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                "version": "V3.1.6",
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            "vendor": "Siemens",
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                "version": "V3.1.5",
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        ],
        "providerMetadata": {
          "dateUpdated": "2026-09-08T08:47:59.039Z",
          "orgId": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e",
          "shortName": "siemens-SADP"
        },
        "references": [
          {
            "url": "https://cert-portal.siemens.com/productcert/html/ssa-082556.html"
          },
          {
            "url": "https://cert-portal.siemens.com/productcert/html/ssa-019113.html"
          }
        ],
        "x_adpType": "supplier"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/mptcp/protocol.c",
            "net/mptcp/protocol.h",
            "net/mptcp/subflow.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "f6e1f25fa5e733570f6d6fe37a4dfed2a0deba47",
              "status": "affected",
              "version": "b19bc2945b40b9fd38e835700907ffe8534ef0de",
              "versionType": "git"
            },
            {
              "lessThan": "fb1f54b7d16f393b8b65d328410f78b4beea8fcc",
              "status": "affected",
              "version": "b19bc2945b40b9fd38e835700907ffe8534ef0de",
              "versionType": "git"
            },
            {
              "lessThan": "3fd6547f5b8ac99687be6d937a0321efda760597",
              "status": "affected",
              "version": "b19bc2945b40b9fd38e835700907ffe8534ef0de",
              "versionType": "git"
            },
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              "status": "affected",
              "version": "b19bc2945b40b9fd38e835700907ffe8534ef0de",
              "versionType": "git"
            },
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              "lessThan": "15fa9ead4d5e6b6b9c794e84144146c917f2cb62",
              "status": "affected",
              "version": "b19bc2945b40b9fd38e835700907ffe8534ef0de",
              "versionType": "git"
            },
            {
              "lessThan": "b313e9037d98c13938740e5ebda7852929366dff",
              "status": "affected",
              "version": "b19bc2945b40b9fd38e835700907ffe8534ef0de",
              "versionType": "git"
            },
            {
              "lessThan": "9b55b253907e7431210483519c5ad711a37dafa1",
              "status": "affected",
              "version": "b19bc2945b40b9fd38e835700907ffe8534ef0de",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/mptcp/protocol.c",
            "net/mptcp/protocol.h",
            "net/mptcp/subflow.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.12"
            },
            {
              "lessThan": "5.12",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.203",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.169",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.135",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.82",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.23",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.19.*",
              "status": "unaffected",
              "version": "6.19.13",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.0",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.15.203",
                  "versionStartIncluding": "5.12",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.1.169",
                  "versionStartIncluding": "5.12",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.135",
                  "versionStartIncluding": "5.12",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.82",
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                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.23",
                  "versionStartIncluding": "5.12",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.19.13",
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                  "versionEndExcluding": "7.0",
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                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
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        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: fix slab-use-after-free in __inet_lookup_established\n\nThe ehash table lookups are lockless and rely on\nSLAB_TYPESAFE_BY_RCU to guarantee socket memory stability\nduring RCU read-side critical sections. Both tcp_prot and\ntcpv6_prot have their slab caches created with this flag\nvia proto_register().\n\nHowever, MPTCP\u0027s mptcp_subflow_init() copies tcpv6_prot into\ntcpv6_prot_override during inet_init() (fs_initcall, level 5),\nbefore inet6_init() (module_init/device_initcall, level 6) has\ncalled proto_register(\u0026tcpv6_prot). At that point,\ntcpv6_prot.slab is still NULL, so tcpv6_prot_override.slab\nremains NULL permanently.\n\nThis causes MPTCP v6 subflow child sockets to be allocated via\nkmalloc (falling into kmalloc-4k) instead of the TCPv6 slab\ncache. The kmalloc-4k cache lacks SLAB_TYPESAFE_BY_RCU, so\nwhen these sockets are freed without SOCK_RCU_FREE (which is\ncleared for child sockets by design), the memory can be\nimmediately reused. Concurrent ehash lookups under\nrcu_read_lock can then access freed memory, triggering a\nslab-use-after-free in __inet_lookup_established.\n\nFix this by splitting the IPv6-specific initialization out of\nmptcp_subflow_init() into a new mptcp_subflow_v6_init(), called\nfrom mptcp_proto_v6_init() before protocol registration. This\nensures tcpv6_prot_override.slab correctly inherits the\nSLAB_TYPESAFE_BY_RCU slab cache."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 9.8,
            "baseSeverity": "CRITICAL",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:N - Remote IPv6 TCP/MPTCP packets reach `tcp_v6_rcv()` and its lockless established-socket ehash lookup through the normal network receive path. A reachable IPv6 MPTCP service can be exercised over the network without local execution.\nAC:L - The vulnerability is a race between freeing an MPTCP IPv6 child socket and concurrent ehash lookup, but the attacker can drive both sides by repeatedly creating/closing MPTCP connections or subflows while sending packets. Under the required rule, this attacker-controlled race is Low complexity.\nPR:N - No local account, capability, namespace setup, or protocol authentication is needed to send the packets that reach the vulnerable receive path. The only environmental requirement is a reachable MPTCP IPv6 listener.\nUI:N - No victim user action is required after the vulnerable service is listening. Network traffic alone can trigger allocation, teardown, and lookup of the affected sockets.\nS:U - The flaw is in the kernel networking stack and impacts kernel-managed resources within the same security authority. It is not a VM escape, IOMMU bypass, or cross-scope boundary violation.\nC:H - This is a kernel heap use-after-free where freed socket memory can be immediately reused while lockless lookup still dereferences it. Such UAF conditions are defensibly capable of exposing kernel memory or primitives useful for broader disclosure.\nI:H - The stale socket pointer can reference attacker-influenced reused kmalloc memory during refcounting and socket processing. Kernel heap UAF is treated as high integrity impact because it can plausibly be developed into write/control-flow corruption.\nA:H - The reported condition is a slab-use-after-free in `__inet_lookup_established`, which can crash or oops the kernel. A remote attacker can trigger it repeatedly against a reachable affected service."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T12:24:19.282Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/f6e1f25fa5e733570f6d6fe37a4dfed2a0deba47"
        },
        {
          "url": "https://git.kernel.org/stable/c/fb1f54b7d16f393b8b65d328410f78b4beea8fcc"
        },
        {
          "url": "https://git.kernel.org/stable/c/3fd6547f5b8ac99687be6d937a0321efda760597"
        },
        {
          "url": "https://git.kernel.org/stable/c/eb9c6aeb512f877cf397deb1e4526f646c70e4a7"
        },
        {
          "url": "https://git.kernel.org/stable/c/15fa9ead4d5e6b6b9c794e84144146c917f2cb62"
        },
        {
          "url": "https://git.kernel.org/stable/c/b313e9037d98c13938740e5ebda7852929366dff"
        },
        {
          "url": "https://git.kernel.org/stable/c/9b55b253907e7431210483519c5ad711a37dafa1"
        }
      ],
      "title": "mptcp: fix slab-use-after-free in __inet_lookup_established",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-31669",
    "datePublished": "2026-04-24T14:45:17.295Z",
    "dateReserved": "2026-03-09T15:48:24.130Z",
    "dateUpdated": "2026-09-08T08:47:59.039Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

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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.
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Action not permitted

BDU:2026-10731 (CVE-2026-31669)

CVE-2026-31669 (GCVE-0-2026-31669)

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