Vulnerability-Lookup

BDU:2026-16638 (CVE-2026-74284)

Vulnerability from fstec – Published: 2026-10-16 – Updated: 2026-10-16 – View on bdu.fstec.ru Fixed

Title

Уязвимость функции update_vf() компонента net/sched/sch_hfsc.c ядра операционной системы Linux, позволяющая нарушителю вызвать отказ в обслуживании

Summary

Уязвимость функции update_vf() компонента net/sched/sch_hfsc.c ядра операционной системы Linux связана с реализацией некорректного потока управления. Эксплуатация уязвимости может позволить нарушителю вызвать отказ в обслуживании

Severity

4.6 (Medium) CVSS 2.0


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

5.5 (Medium) CVSS 3.1


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

Class

Code vulnerability

Status

Confirmed by the vendor

Exploitation

Data structure manipulation

Incidents

Being clarified

Remediation

Software update

CWE

CWE-691 - Недостаточное управление потоком

Aliases

CVE-2026-74284, GHSA-MFHV-3JVW-9W4G

References

16 references

URL
https://git.kernel.org/stable/c/15720cd8fa3fc625146128f89a8e11b0449a20a7
https://git.kernel.org/stable/c/3a49bbae676fef1ffe548971e6229ae2adeb9d10
https://git.kernel.org/stable/c/66dbb13eeb2fc339f8f548a9076be4c1a94857b0
https://git.kernel.org/stable/c/90b662ea25f5e83bb3b8ccec5b93ced810b92fb8
https://git.kernel.org/stable/c/9221a594c72a1446137926d4c2aa04e345f798dc
https://git.kernel.org/stable/c/a425c82ff06cda5165e0de3de8c2a445ec1f863e
https://git.kernel.org/stable/c/b2a017bfcf565721918ec7355a373911d2f2a227
https://git.kernel.org/stable/c/fc973ecd1a079b9a87c360478542f3a56dea085b
https://github.com/advisories/GHSA-mfhv-3jvw-9w4g
http://repo.red-soft.ru/redos/7.3c/x86_64/updates/
http://repo.red-soft.ru/redos/8.0/x86_64/updates/
http://repo.red-soft.ru/redos/8.0/aarch64/updates/
https://security-tracker.debian.org/tracker/CVE-2026-74284
https://deb.freexian.com/extended-lts/tracker/CVE-2026-74284
https://access.redhat.com/security/cve/CVE-2026-74284
https://ubuntu.com/security/CVE-2026-74284

Impacted products

5 products from 5 vendors

Vendors

Red Hat, Inc., Canonical Ltd., Сообщество свободного программного обеспечения, ООО «Ред Софт»

Products

Red Hat Enterprise Linux, Ubuntu, Debian GNU/Linux, РЕД ОС (запись в едином реестре российских программ №3751), Linux

Versions

7 (Red Hat Enterprise Linux), 16.04 LTS (Ubuntu), 9 (Debian GNU/Linux), 18.04 LTS (Ubuntu), 8 (Red Hat Enterprise Linux), 10 (Debian GNU/Linux), 20.04 LTS (Ubuntu), 11 (Debian GNU/Linux), 12 (Debian GNU/Linux), 7.3 (РЕД ОС), 22.04 LTS (Ubuntu), 9 (Red Hat Enterprise Linux), 24.04 LTS (Ubuntu), 10 (Red Hat Enterprise Linux), 13 (Debian GNU/Linux), 8.0 (РЕД ОС), от 5.4.297 до 5.5 (Linux), 26.04 LTS (Ubuntu), от 6.19 до 7.1.5 (Linux), от 5.10.241 до 5.10.261 (Linux), от 5.15.190 до 5.15.212 (Linux), от 6.1.138 до 6.1.178 (Linux), от 6.6.90 до 6.6.145 (Linux), от 6.12.28 до 6.12.97 (Linux), от 6.14.6 до 6.18.40 (Linux)

Product types

Operating system

Platforms

Red Hat, Inc. Red Hat Enterprise Linux 7, Canonical Ltd. Ubuntu 16.04 LTS, Сообщество свободного программного обеспечения Debian GNU/Linux 9, Canonical Ltd. Ubuntu 18.04 LTS, Inc. Red Hat Enterprise Linux 8, Сообщество свободного программного обеспечения Debian GNU/Linux 10, Canonical Ltd. Ubuntu 20.04 LTS, Сообщество свободного программного обеспечения Debian GNU/Linux 11, Сообщество свободного программного обеспечения Debian GNU/Linux 12, ООО «Ред Софт» РЕД ОС 7.3 (запись в едином реестре российских программ №3751), Canonical Ltd. Ubuntu 22.04 LTS, Inc. Red Hat Enterprise Linux 9, Canonical Ltd. Ubuntu 24.04 LTS, Inc. Red Hat Enterprise Linux 10, Сообщество свободного программного обеспечения Debian GNU/Linux 13, ООО «Ред Софт» РЕД ОС 8.0 (запись в едином реестре российских программ №3751), Сообщество свободного программного обеспечения Linux от 5.4.297 до 5.5, Canonical Ltd. Ubuntu 26.04 LTS, Сообщество свободного программного обеспечения Linux от 6.19 до 7.1.5, Сообщество свободного программного обеспечения Linux от 5.10.241 до 5.10.261, Сообщество свободного программного обеспечения Linux от 5.15.190 до 5.15.212, Сообщество свободного программного обеспечения Linux от 6.1.138 до 6.1.178, Сообщество свободного программного обеспечения Linux от 6.6.90 до 6.6.145, Сообщество свободного программного обеспечения Linux от 6.12.28 до 6.12.97, Сообщество свободного программного обеспечения Linux от 6.14.6 до 6.18.40

Mitigations

Использование рекомендаций: Для Linux: https://git.kernel.org/stable/c/15720cd8fa3fc625146128f89a8e11b0449a20a7 https://git.kernel.org/stable/c/3a49bbae676fef1ffe548971e6229ae2adeb9d10 https://git.kernel.org/stable/c/66dbb13eeb2fc339f8f548a9076be4c1a94857b0 https://git.kernel.org/stable/c/90b662ea25f5e83bb3b8ccec5b93ced810b92fb8 https://git.kernel.org/stable/c/9221a594c72a1446137926d4c2aa04e345f798dc https://git.kernel.org/stable/c/a425c82ff06cda5165e0de3de8c2a445ec1f863e https://git.kernel.org/stable/c/b2a017bfcf565721918ec7355a373911d2f2a227 https://git.kernel.org/stable/c/fc973ecd1a079b9a87c360478542f3a56dea085b Для Ред ОС: http://repo.red-soft.ru/redos/7.3c/x86_64/updates/ http://repo.red-soft.ru/redos/8.0/x86_64/updates/ http://repo.red-soft.ru/redos/8.0/aarch64/updates/ Для Debian GNU/Linux: https://security-tracker.debian.org/tracker/CVE-2026-74284 https://deb.freexian.com/extended-lts/tracker/CVE-2026-74284 Для программных продуктов Red Hat Inc.: https://access.redhat.com/security/cve/CVE-2026-74284 Для Ubuntu: https://ubuntu.com/security/CVE-2026-74284

JSON

To clipboard

{
  "CVSS 2.0": "AV:L/AC:L/Au:S/C:N/I:N/A:C",
  "CVSS 3.0": "AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/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., Canonical Ltd., \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\u0435\u0434 \u0421\u043e\u0444\u0442\u00bb",
  "\u0412\u0435\u0440\u0441\u0438\u044f \u041f\u041e": "7 (Red Hat Enterprise Linux), 16.04 LTS (Ubuntu), 9 (Debian GNU/Linux), 18.04 LTS (Ubuntu), 8 (Red Hat Enterprise Linux), 10 (Debian GNU/Linux), 20.04 LTS (Ubuntu), 11 (Debian GNU/Linux), 12 (Debian GNU/Linux), 7.3 (\u0420\u0415\u0414 \u041e\u0421), 22.04 LTS (Ubuntu), 9 (Red Hat Enterprise Linux), 24.04 LTS (Ubuntu), 10 (Red Hat Enterprise Linux), 13 (Debian GNU/Linux), 8.0 (\u0420\u0415\u0414 \u041e\u0421), \u043e\u0442 5.4.297 \u0434\u043e 5.5 (Linux), 26.04 LTS (Ubuntu), \u043e\u0442 6.19 \u0434\u043e 7.1.5 (Linux), \u043e\u0442 5.10.241 \u0434\u043e 5.10.261 (Linux), \u043e\u0442 5.15.190 \u0434\u043e 5.15.212 (Linux), \u043e\u0442 6.1.138 \u0434\u043e 6.1.178 (Linux), \u043e\u0442 6.6.90 \u0434\u043e 6.6.145 (Linux), \u043e\u0442 6.12.28 \u0434\u043e 6.12.97 (Linux), \u043e\u0442 6.14.6 \u0434\u043e 6.18.40 (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": "\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://git.kernel.org/stable/c/15720cd8fa3fc625146128f89a8e11b0449a20a7\nhttps://git.kernel.org/stable/c/3a49bbae676fef1ffe548971e6229ae2adeb9d10\nhttps://git.kernel.org/stable/c/66dbb13eeb2fc339f8f548a9076be4c1a94857b0\nhttps://git.kernel.org/stable/c/90b662ea25f5e83bb3b8ccec5b93ced810b92fb8\nhttps://git.kernel.org/stable/c/9221a594c72a1446137926d4c2aa04e345f798dc\nhttps://git.kernel.org/stable/c/a425c82ff06cda5165e0de3de8c2a445ec1f863e\nhttps://git.kernel.org/stable/c/b2a017bfcf565721918ec7355a373911d2f2a227\nhttps://git.kernel.org/stable/c/fc973ecd1a079b9a87c360478542f3a56dea085b\n\n\u0414\u043b\u044f \u0420\u0435\u0434 \u041e\u0421:\nhttp://repo.red-soft.ru/redos/7.3c/x86_64/updates/\nhttp://repo.red-soft.ru/redos/8.0/x86_64/updates/\nhttp://repo.red-soft.ru/redos/8.0/aarch64/updates/\n\n\u0414\u043b\u044f Debian GNU/Linux:\nhttps://security-tracker.debian.org/tracker/CVE-2026-74284\nhttps://deb.freexian.com/extended-lts/tracker/CVE-2026-74284\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-2026-74284\n\n\u0414\u043b\u044f Ubuntu:\nhttps://ubuntu.com/security/CVE-2026-74284",
  "\u0414\u0430\u0442\u0430 \u0432\u044b\u044f\u0432\u043b\u0435\u043d\u0438\u044f": "10.06.2026",
  "\u0414\u0430\u0442\u0430 \u043f\u043e\u0441\u043b\u0435\u0434\u043d\u0435\u0433\u043e \u043e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u044f": "16.10.2026",
  "\u0414\u0430\u0442\u0430 \u043f\u0443\u0431\u043b\u0438\u043a\u0430\u0446\u0438\u0438": "16.10.2026",
  "\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440": "BDU:2026-16638",
  "\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-2026-74284, GHSA-MFHV-3JVW-9W4G",
  "\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, Ubuntu, Debian GNU/Linux, \u0420\u0415\u0414 \u041e\u0421 (\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 \u21163751), 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 , Canonical Ltd. Ubuntu 16.04 LTS , \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 9 , Canonical Ltd. Ubuntu 18.04 LTS , 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 10 , Canonical Ltd. Ubuntu 20.04 LTS , \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\u0435\u0434 \u0421\u043e\u0444\u0442\u00bb \u0420\u0415\u0414 \u041e\u0421 7.3  (\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 \u21163751), Canonical Ltd. Ubuntu 22.04 LTS , Red Hat, Inc. Red Hat Enterprise Linux 9 , Canonical Ltd. Ubuntu 24.04 LTS , 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 , \u041e\u041e\u041e \u00ab\u0420\u0435\u0434 \u0421\u043e\u0444\u0442\u00bb \u0420\u0415\u0414 \u041e\u0421 8.0  (\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 \u21163751), \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 5.4.297 \u0434\u043e 5.5 , Canonical Ltd. Ubuntu 26.04 LTS , \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 7.1.5 , \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 5.10.241 \u0434\u043e 5.10.261 , \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 5.15.190 \u0434\u043e 5.15.212 , \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 6.1.138 \u0434\u043e 6.1.178 , \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 6.6.90 \u0434\u043e 6.6.145 , \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 6.12.28 \u0434\u043e 6.12.97 , \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 6.14.6 \u0434\u043e 6.18.40 ",
  "\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 update_vf() \u043a\u043e\u043c\u043f\u043e\u043d\u0435\u043d\u0442\u0430 net/sched/sch_hfsc.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 \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": "\u041d\u0435\u0434\u043e\u0441\u0442\u0430\u0442\u043e\u0447\u043d\u043e\u0435 \u0443\u043f\u0440\u0430\u0432\u043b\u0435\u043d\u0438\u0435 \u043f\u043e\u0442\u043e\u043a\u043e\u043c (CWE-691)",
  "\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 update_vf() \u043a\u043e\u043c\u043f\u043e\u043d\u0435\u043d\u0442\u0430 net/sched/sch_hfsc.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 \u0440\u0435\u0430\u043b\u0438\u0437\u0430\u0446\u0438\u0435\u0439 \u043d\u0435\u043a\u043e\u0440\u0440\u0435\u043a\u0442\u043d\u043e\u0433\u043e \u043f\u043e\u0442\u043e\u043a\u0430 \u0443\u043f\u0440\u0430\u0432\u043b\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",
  "\u0421\u0441\u044b\u043b\u043a\u0438 \u043d\u0430 \u0438\u0441\u0442\u043e\u0447\u043d\u0438\u043a\u0438": "https://git.kernel.org/stable/c/15720cd8fa3fc625146128f89a8e11b0449a20a7\nhttps://git.kernel.org/stable/c/3a49bbae676fef1ffe548971e6229ae2adeb9d10\nhttps://git.kernel.org/stable/c/66dbb13eeb2fc339f8f548a9076be4c1a94857b0\nhttps://git.kernel.org/stable/c/90b662ea25f5e83bb3b8ccec5b93ced810b92fb8\nhttps://git.kernel.org/stable/c/9221a594c72a1446137926d4c2aa04e345f798dc\nhttps://git.kernel.org/stable/c/a425c82ff06cda5165e0de3de8c2a445ec1f863e\nhttps://git.kernel.org/stable/c/b2a017bfcf565721918ec7355a373911d2f2a227\nhttps://git.kernel.org/stable/c/fc973ecd1a079b9a87c360478542f3a56dea085b\nhttps://github.com/advisories/GHSA-mfhv-3jvw-9w4g\nhttp://repo.red-soft.ru/redos/7.3c/x86_64/updates/\nhttp://repo.red-soft.ru/redos/8.0/x86_64/updates/\nhttp://repo.red-soft.ru/redos/8.0/aarch64/updates/\nhttps://security-tracker.debian.org/tracker/CVE-2026-74284\nhttps://deb.freexian.com/extended-lts/tracker/CVE-2026-74284\nhttps://access.redhat.com/security/cve/CVE-2026-74284\nhttps://ubuntu.com/security/CVE-2026-74284",
  "\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-691",
  "\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 4,6)\n\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 3.1 \u0441\u043e\u0441\u0442\u0430\u0432\u043b\u044f\u0435\u0442 5,5)"
}

CVE-2026-74284 (GCVE-0-2026-74284)

Vulnerability from cvelistv5 – Published: 2026-08-15 05:57 – Updated: 2026-08-17 05:16

Title

net/sched: sch_hfsc: Don't make class passive twice

Summary

In the Linux kernel, the following vulnerability has been resolved: net/sched: sch_hfsc: Don't make class passive twice update_vf() is called from two places for the same class during a single dequeue when the class's child qdisc (e.g. codel/fq_codel) drops its last packets while dequeuing: 1. The child calls qdisc_tree_reduce_backlog(), which, now that the child is empty, invokes hfsc_qlen_notify() -> update_vf(cl, 0, 0) and turns the class passive (cl_nactive is decremented up the hierarchy). 2. hfsc_dequeue() then calls update_vf(cl, qdisc_pkt_len(skb), cur_time) to charge the dequeued bytes. On the second call the class is already passive, but its child qdisc is still empty, so update_vf() arms go_passive again: if (cl->qdisc->q.qlen == 0 && cl->cl_flags & HFSC_FSC) go_passive = 1; The leaf is then skipped by the cl_nactive == 0 check inside the loop, which does not clear go_passive, so the stale go_passive propagates to the parent and decrements its cl_nactive a second time. A parent that still has other active children is driven to cl_nactive == 0 and removed from the vttree, even though those siblings are still backlogged. They are never dequeued again and the qdisc stalls. Fix this by only arming go_passive when the class is actually active, so an already-passive class no longer triggers a second passive transition. The byte accounting (cl->cl_total += len) still runs for every ancestor, so dequeued bytes continue to be counted exactly once.

Severity

No CVSS data available.

Assigner

Linux CNA under the mitre root

CNA scorecard D 53/100 over 6992 records in the last 180 days details

References

8 references

URL	Tags
https://git.kernel.org/stable/c/a425c82ff06cda516…
https://git.kernel.org/stable/c/fc973ecd1a079b9a8…
https://git.kernel.org/stable/c/15720cd8fa3fc6251…
https://git.kernel.org/stable/c/b2a017bfcf5657219…
https://git.kernel.org/stable/c/9221a594c72a14461…
https://git.kernel.org/stable/c/66dbb13eeb2fc339f…
https://git.kernel.org/stable/c/3a49bbae676fef1ff…
https://git.kernel.org/stable/c/90b662ea25f5e83bb…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 72c61ffbeeb8c50f6d4d70c65d3283aa1bac57a7 , < a425c82ff06cda5165e0de3de8c2a445ec1f863e (git) Affected: a5efc95a33bd4fcb879250852828cc58c7862970 , < fc973ecd1a079b9a87c360478542f3a56dea085b (git) Affected: 0475c85426b18eccdcb7f9fb58d8f8e9c6c58c87 , < 15720cd8fa3fc625146128f89a8e11b0449a20a7 (git) Affected: 9030a91235ae4845ec71902c3e0cecfc9ed1f2df , < b2a017bfcf565721918ec7355a373911d2f2a227 (git) Affected: d06476714d2819b550e0cc39222347e2c8941c9d , < 9221a594c72a1446137926d4c2aa04e345f798dc (git) Affected: 51eb3b65544c9efd6a1026889ee5fb5aa62da3bb , < 66dbb13eeb2fc339f8f548a9076be4c1a94857b0 (git) Affected: 51eb3b65544c9efd6a1026889ee5fb5aa62da3bb , < 3a49bbae676fef1ffe548971e6229ae2adeb9d10 (git) Affected: 51eb3b65544c9efd6a1026889ee5fb5aa62da3bb , < 90b662ea25f5e83bb3b8ccec5b93ced810b92fb8 (git) Affected: 9a5fd5c2f4d4afdd5e405083ee53e0789ce76956 (git) Affected: c1175c4ad01dbc9c979d099861fa90a754f72059 (git) Affected: 5.10.241 , < 5.10.261 (semver) Affected: 5.15.190 , < 5.15.212 (semver) Affected: 6.1.138 , < 6.1.178 (semver) Affected: 6.6.90 , < 6.6.145 (semver) Affected: 6.12.28 , < 6.12.97 (semver) Affected: 5.4.297 , < 5.5 (semver) Affected: 6.14.6 , < 6.15 (semver)
Linux	Linux	Affected: 6.15 Unaffected: 0 , < 6.15 (semver) Unaffected: 5.10.261 , ≤ 5.10.* (semver) Unaffected: 5.15.212 , ≤ 5.15.* (semver) Unaffected: 6.1.178 , ≤ 6.1.* (semver) Unaffected: 6.6.145 , ≤ 6.6.* (semver) Unaffected: 6.12.97 , ≤ 6.12.* (semver) Unaffected: 6.18.40 , ≤ 6.18.* (semver) Unaffected: 7.1.5 , ≤ 7.1.* (semver) Unaffected: 7.2 , ≤ * (original_commit_for_fix)

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{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/sched/sch_hfsc.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "a425c82ff06cda5165e0de3de8c2a445ec1f863e",
              "status": "affected",
              "version": "72c61ffbeeb8c50f6d4d70c65d3283aa1bac57a7",
              "versionType": "git"
            },
            {
              "lessThan": "fc973ecd1a079b9a87c360478542f3a56dea085b",
              "status": "affected",
              "version": "a5efc95a33bd4fcb879250852828cc58c7862970",
              "versionType": "git"
            },
            {
              "lessThan": "15720cd8fa3fc625146128f89a8e11b0449a20a7",
              "status": "affected",
              "version": "0475c85426b18eccdcb7f9fb58d8f8e9c6c58c87",
              "versionType": "git"
            },
            {
              "lessThan": "b2a017bfcf565721918ec7355a373911d2f2a227",
              "status": "affected",
              "version": "9030a91235ae4845ec71902c3e0cecfc9ed1f2df",
              "versionType": "git"
            },
            {
              "lessThan": "9221a594c72a1446137926d4c2aa04e345f798dc",
              "status": "affected",
              "version": "d06476714d2819b550e0cc39222347e2c8941c9d",
              "versionType": "git"
            },
            {
              "lessThan": "66dbb13eeb2fc339f8f548a9076be4c1a94857b0",
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          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: sch_hfsc: Don\u0027t make class passive twice\n\nupdate_vf() is called from two places for the same class during a single\ndequeue when the class\u0027s child qdisc (e.g. codel/fq_codel) drops its last\npackets while dequeuing:\n\n1. The child calls qdisc_tree_reduce_backlog(), which, now that the child\n   is empty, invokes hfsc_qlen_notify() -\u003e update_vf(cl, 0, 0) and turns\n   the class passive (cl_nactive is decremented up the hierarchy).\n\n2. hfsc_dequeue() then calls update_vf(cl, qdisc_pkt_len(skb), cur_time)\n   to charge the dequeued bytes.\n\nOn the second call the class is already passive, but its child qdisc is\nstill empty, so update_vf() arms go_passive again:\n\n      if (cl-\u003eqdisc-\u003eq.qlen == 0 \u0026\u0026 cl-\u003ecl_flags \u0026 HFSC_FSC)\n              go_passive = 1;\n\nThe leaf is then skipped by the cl_nactive == 0 check inside the loop,\nwhich does not clear go_passive, so the stale go_passive propagates to the\nparent and decrements its cl_nactive a second time. A parent that still\nhas other active children is driven to cl_nactive == 0 and removed from\nthe vttree, even though those siblings are still backlogged. They are\nnever dequeued again and the qdisc stalls.\n\nFix this by only arming go_passive when the class is actually active, so an\nalready-passive class no longer triggers a second passive transition. The\nbyte accounting (cl-\u003ecl_total += len) still runs for every ancestor, so\ndequeued bytes continue to be counted exactly once."
        }
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      ],
      "title": "net/sched: sch_hfsc: Don\u0027t make class passive twice",
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    "assignerShortName": "Linux",
    "cveId": "CVE-2026-74284",
    "datePublished": "2026-08-15T05:57:53.290Z",
    "dateReserved": "2026-08-15T05:44:03.881Z",
    "dateUpdated": "2026-08-17T05:16:29.785Z",
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}

GHSA-MFHV-3JVW-9W4G

Vulnerability from github – Published: 2026-08-15 06:32 – Updated: 2026-08-15 06:32

Details

In the Linux kernel, the following vulnerability has been resolved:

net/sched: sch_hfsc: Don't make class passive twice

update_vf() is called from two places for the same class during a single dequeue when the class's child qdisc (e.g. codel/fq_codel) drops its last packets while dequeuing:

The child calls qdisc_tree_reduce_backlog(), which, now that the child is empty, invokes hfsc_qlen_notify() -> update_vf(cl, 0, 0) and turns the class passive (cl_nactive is decremented up the hierarchy).
hfsc_dequeue() then calls update_vf(cl, qdisc_pkt_len(skb), cur_time) to charge the dequeued bytes.

On the second call the class is already passive, but its child qdisc is still empty, so update_vf() arms go_passive again:

  if (cl->qdisc->q.qlen == 0 && cl->cl_flags & HFSC_FSC)
          go_passive = 1;

The leaf is then skipped by the cl_nactive == 0 check inside the loop, which does not clear go_passive, so the stale go_passive propagates to the parent and decrements its cl_nactive a second time. A parent that still has other active children is driven to cl_nactive == 0 and removed from the vttree, even though those siblings are still backlogged. They are never dequeued again and the qdisc stalls.

Fix this by only arming go_passive when the class is actually active, so an already-passive class no longer triggers a second passive transition. The byte accounting (cl->cl_total += len) still runs for every ancestor, so dequeued bytes continue to be counted exactly once.

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{
  "affected": [],
  "aliases": [
    "CVE-2026-74284"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-15T06:22:27Z",
    "severity": null
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: sch_hfsc: Don\u0027t make class passive twice\n\nupdate_vf() is called from two places for the same class during a single\ndequeue when the class\u0027s child qdisc (e.g. codel/fq_codel) drops its last\npackets while dequeuing:\n\n1. The child calls qdisc_tree_reduce_backlog(), which, now that the child\n   is empty, invokes hfsc_qlen_notify() -\u003e update_vf(cl, 0, 0) and turns\n   the class passive (cl_nactive is decremented up the hierarchy).\n\n2. hfsc_dequeue() then calls update_vf(cl, qdisc_pkt_len(skb), cur_time)\n   to charge the dequeued bytes.\n\nOn the second call the class is already passive, but its child qdisc is\nstill empty, so update_vf() arms go_passive again:\n\n      if (cl-\u003eqdisc-\u003eq.qlen == 0 \u0026\u0026 cl-\u003ecl_flags \u0026 HFSC_FSC)\n              go_passive = 1;\n\nThe leaf is then skipped by the cl_nactive == 0 check inside the loop,\nwhich does not clear go_passive, so the stale go_passive propagates to the\nparent and decrements its cl_nactive a second time. A parent that still\nhas other active children is driven to cl_nactive == 0 and removed from\nthe vttree, even though those siblings are still backlogged. They are\nnever dequeued again and the qdisc stalls.\n\nFix this by only arming go_passive when the class is actually active, so an\nalready-passive class no longer triggers a second passive transition. The\nbyte accounting (cl-\u003ecl_total += len) still runs for every ancestor, so\ndequeued bytes continue to be counted exactly once.",
  "id": "GHSA-mfhv-3jvw-9w4g",
  "modified": "2026-08-15T06:32:28Z",
  "published": "2026-08-15T06:32:28Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-74284"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/15720cd8fa3fc625146128f89a8e11b0449a20a7"
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  "schema_version": "1.4.0",
  "severity": []
}

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BDU:2026-16638 (CVE-2026-74284)

CVE-2026-74284 (GCVE-0-2026-74284)

GHSA-MFHV-3JVW-9W4G

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