Vulnerability-Lookup

BDU:2026-12527 (CVE-2026-31476)

Vulnerability from fstec – Published: 2026-08-25 – Updated: 2026-09-07 – View on bdu.fstec.ru Fixed

Title

Уязвимость функции smb2_sess_setup() модуля fs/smb/server/smb2pdu.c файловой системы Smb ядра операционной системы Linux, позволяющая нарушителю оказать воздействие на целостность защищаемой информации или вызвать отказ в обслуживании

Summary

Уязвимость функции smb2_sess_setup() модуля fs/smb/server/smb2pdu.c файловой системы Smb ядра операционной системы Linux связана с недостатками разграничения доступа. Эксплуатация уязвимости может позволить нарушителю, действующему удалённо, оказать воздействие на целостность защищаемой информации или вызвать отказ в обслуживании

Severity

8.5 (High) CVSS 2.0


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

8.2 (High) CVSS 3.1


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

Class

Multi-factor vulnerability

Status

Confirmed by the vendor

Exploitation

Authorization bypass, Resource exhaustion

Incidents

Being clarified

Remediation

Software update

CWE

CWE-274 - Неправильная обработка недостаточных привилегий
CWE-404 - Некорректная зачистка или освобождение ресурсов

Aliases

CVE-2026-31476

References

10 references

URL
https://git.kernel.org/stable/c/e0e5edc81b241c70355217de7e120c97c3429deb
https://git.kernel.org/stable/c/6fafc4c4238e538969f1375f9ecdc6587c53f1cc
https://git.kernel.org/stable/c/f5300690c23c5ac860499bb37dbc09cf43fd62e6
https://git.kernel.org/stable/c/1d1888b4a7aec518b707f6eca0bf08992c0e8da3
https://git.kernel.org/stable/c/a897064a457056acb976e20e3007cdf553de340f
https://www.cve.org/CVERecord?id=CVE-2026-31476
https://git.kernel.org/linus/9bbb19d21ded7d78645506f20d8c44895e3d0fb9
https://security-tracker.debian.org/tracker/CVE-2026-31476
https://ubuntu.com/security/CVE-2026-31476
https://altsp.su/obnovleniya-bezopasnosti/

Impacted products

4 products from 3 vendors

Vendors

Canonical Ltd., Сообщество свободного программного обеспечения, АО «ИВК»

Products

Ubuntu, Debian GNU/Linux, АЛЬТ СП 10, Linux

Versions

20.04 LTS (Ubuntu), 11 (Debian GNU/Linux), 12 (Debian GNU/Linux), 22.04 LTS (Ubuntu), - (АЛЬТ СП 10), 24.04 LTS (Ubuntu), 13 (Debian GNU/Linux), от 6.19 до 6.19.10 включительно (Linux), от 6.2 до 6.6.130 включительно (Linux), от 6.7 до 6.12.79 включительно (Linux), от 6.13 до 6.18.20 включительно (Linux), от 5.15 до 6.1.167 включительно (Linux)

Product types

Operating system

Platforms

Canonical Ltd. Ubuntu 20.04 LTS, Сообщество свободного программного обеспечения Debian GNU/Linux 11, Сообщество свободного программного обеспечения Debian GNU/Linux 12, Canonical Ltd. Ubuntu 22.04 LTS, АО «ИВК» АЛЬТ СП 10 -, Canonical Ltd. Ubuntu 24.04 LTS, Сообщество свободного программного обеспечения Debian GNU/Linux 13, Сообщество свободного программного обеспечения Linux от 6.19 до 6.19.10 включительно, Сообщество свободного программного обеспечения Linux от 6.2 до 6.6.130 включительно, Сообщество свободного программного обеспечения Linux от 6.7 до 6.12.79 включительно, Сообщество свободного программного обеспечения Linux от 6.13 до 6.18.20 включительно, Сообщество свободного программного обеспечения Linux от 5.15 до 6.1.167 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://git.kernel.org/stable/c/e0e5edc81b241c70355217de7e120c97c3429deb https://git.kernel.org/stable/c/6fafc4c4238e538969f1375f9ecdc6587c53f1cc https://git.kernel.org/stable/c/f5300690c23c5ac860499bb37dbc09cf43fd62e6 https://git.kernel.org/stable/c/1d1888b4a7aec518b707f6eca0bf08992c0e8da3 https://git.kernel.org/stable/c/a897064a457056acb976e20e3007cdf553de340f https://git.kernel.org/linus/9bbb19d21ded7d78645506f20d8c44895e3d0fb9 Для Debian GNU/Linux: https://security-tracker.debian.org/tracker/CVE-2026-31476 Для Ubuntu: https://ubuntu.com/security/CVE-2026-31476 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:N/I:P/A:C",
  "CVSS 3.0": "AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H",
  "CVSS 4.0": null,
  "remediation_\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440": null,
  "remediation_\u041d\u0430\u0438\u043c\u0435\u043d\u043e\u0432\u0430\u043d\u0438\u0435": null,
  "\u0412\u0435\u043d\u0434\u043e\u0440 \u041f\u041e": "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, \u0410\u041e \u00ab\u0418\u0412\u041a\u00bb",
  "\u0412\u0435\u0440\u0441\u0438\u044f \u041f\u041e": "20.04 LTS (Ubuntu), 11 (Debian GNU/Linux), 12 (Debian GNU/Linux), 22.04 LTS (Ubuntu), - (\u0410\u041b\u042c\u0422 \u0421\u041f 10), 24.04 LTS (Ubuntu), 13 (Debian GNU/Linux), \u043e\u0442 6.19 \u0434\u043e 6.19.10 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e (Linux), \u043e\u0442 6.2 \u0434\u043e 6.6.130 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e (Linux), \u043e\u0442 6.7 \u0434\u043e 6.12.79 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e (Linux), \u043e\u0442 6.13 \u0434\u043e 6.18.20 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e (Linux), \u043e\u0442 5.15 \u0434\u043e 6.1.167 \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\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/e0e5edc81b241c70355217de7e120c97c3429deb\nhttps://git.kernel.org/stable/c/6fafc4c4238e538969f1375f9ecdc6587c53f1cc\nhttps://git.kernel.org/stable/c/f5300690c23c5ac860499bb37dbc09cf43fd62e6\nhttps://git.kernel.org/stable/c/1d1888b4a7aec518b707f6eca0bf08992c0e8da3\nhttps://git.kernel.org/stable/c/a897064a457056acb976e20e3007cdf553de340f\nhttps://git.kernel.org/linus/9bbb19d21ded7d78645506f20d8c44895e3d0fb9\n\n\u0414\u043b\u044f Debian GNU/Linux:\nhttps://security-tracker.debian.org/tracker/CVE-2026-31476\n\n\u0414\u043b\u044f Ubuntu:\nhttps://ubuntu.com/security/CVE-2026-31476\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": "22.03.2026",
  "\u0414\u0430\u0442\u0430 \u043f\u043e\u0441\u043b\u0435\u0434\u043d\u0435\u0433\u043e \u043e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u044f": "07.09.2026",
  "\u0414\u0430\u0442\u0430 \u043f\u0443\u0431\u043b\u0438\u043a\u0430\u0446\u0438\u0438": "25.08.2026",
  "\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440": "BDU:2026-12527",
  "\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-2026-31476",
  "\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 \u043c\u043d\u043e\u0433\u043e\u0444\u0430\u043a\u0442\u043e\u0440\u043d\u0430\u044f",
  "\u041d\u0430\u0437\u0432\u0430\u043d\u0438\u0435 \u041f\u041e": "Ubuntu, 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": "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 , Canonical Ltd. Ubuntu 22.04 LTS , \u0410\u041e \u00ab\u0418\u0412\u041a\u00bb \u0410\u041b\u042c\u0422 \u0421\u041f 10 - , Canonical Ltd. Ubuntu 24.04 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 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 \u043e\u0442 6.19 \u0434\u043e 6.19.10 \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 6.6.130 \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 6.12.79 \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 6.18.20 \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 5.15 \u0434\u043e 6.1.167 \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 smb2_sess_setup() \u043c\u043e\u0434\u0443\u043b\u044f fs/smb/server/smb2pdu.c \u0444\u0430\u0439\u043b\u043e\u0432\u043e\u0439 \u0441\u0438\u0441\u0442\u0435\u043c\u044b Smb \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 \u0446\u0435\u043b\u043e\u0441\u0442\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 \u0438\u043b\u0438 \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\u043f\u0440\u0430\u0432\u0438\u043b\u044c\u043d\u0430\u044f \u043e\u0431\u0440\u0430\u0431\u043e\u0442\u043a\u0430 \u043d\u0435\u0434\u043e\u0441\u0442\u0430\u0442\u043e\u0447\u043d\u044b\u0445 \u043f\u0440\u0438\u0432\u0438\u043b\u0435\u0433\u0438\u0439 (CWE-274), \u041d\u0435\u043a\u043e\u0440\u0440\u0435\u043a\u0442\u043d\u0430\u044f \u0437\u0430\u0447\u0438\u0441\u0442\u043a\u0430 \u0438\u043b\u0438 \u043e\u0441\u0432\u043e\u0431\u043e\u0436\u0434\u0435\u043d\u0438\u0435 \u0440\u0435\u0441\u0443\u0440\u0441\u043e\u0432 (CWE-404)",
  "\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 smb2_sess_setup() \u043c\u043e\u0434\u0443\u043b\u044f fs/smb/server/smb2pdu.c \u0444\u0430\u0439\u043b\u043e\u0432\u043e\u0439 \u0441\u0438\u0441\u0442\u0435\u043c\u044b Smb \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 \u043d\u0435\u0434\u043e\u0441\u0442\u0430\u0442\u043a\u0430\u043c\u0438 \u0440\u0430\u0437\u0433\u0440\u0430\u043d\u0438\u0447\u0435\u043d\u0438\u044f \u0434\u043e\u0441\u0442\u0443\u043f\u0430. \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, \u0434\u0435\u0439\u0441\u0442\u0432\u0443\u044e\u0449\u0435\u043c\u0443 \u0443\u0434\u0430\u043b\u0451\u043d\u043d\u043e, \u043e\u043a\u0430\u0437\u0430\u0442\u044c \u0432\u043e\u0437\u0434\u0435\u0439\u0441\u0442\u0432\u0438\u0435 \u043d\u0430 \u0446\u0435\u043b\u043e\u0441\u0442\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 \u0438\u043b\u0438 \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": "\u041d\u0430\u0440\u0443\u0448\u0435\u043d\u0438\u0435 \u0430\u0432\u0442\u043e\u0440\u0438\u0437\u0430\u0446\u0438\u0438, \u0418\u0441\u0447\u0435\u0440\u043f\u0430\u043d\u0438\u0435 \u0440\u0435\u0441\u0443\u0440\u0441\u043e\u0432",
  "\u0421\u0441\u044b\u043b\u043a\u0438 \u043d\u0430 \u0438\u0441\u0442\u043e\u0447\u043d\u0438\u043a\u0438": "https://git.kernel.org/stable/c/e0e5edc81b241c70355217de7e120c97c3429deb\nhttps://git.kernel.org/stable/c/6fafc4c4238e538969f1375f9ecdc6587c53f1cc\nhttps://git.kernel.org/stable/c/f5300690c23c5ac860499bb37dbc09cf43fd62e6\nhttps://git.kernel.org/stable/c/1d1888b4a7aec518b707f6eca0bf08992c0e8da3\nhttps://git.kernel.org/stable/c/a897064a457056acb976e20e3007cdf553de340f\nhttps://www.cve.org/CVERecord?id=CVE-2026-31476\nhttps://git.kernel.org/linus/9bbb19d21ded7d78645506f20d8c44895e3d0fb9\nhttps://security-tracker.debian.org/tracker/CVE-2026-31476\nhttps://ubuntu.com/security/CVE-2026-31476\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-274, CWE-404",
  "\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": "\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 2.0 \u0441\u043e\u0441\u0442\u0430\u0432\u043b\u044f\u0435\u0442 8,5)\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 8,2)"
}

CVE-2026-31476 (GCVE-0-2026-31476)

Vulnerability from cvelistv5 – Published: 2026-04-22 13:54 – Updated: 2026-08-05 12:22

Title

ksmbd: do not expire session on binding failure

Summary

In the Linux kernel, the following vulnerability has been resolved: ksmbd: do not expire session on binding failure When a multichannel session binding request fails (e.g. wrong password), the error path unconditionally sets sess->state = SMB2_SESSION_EXPIRED. However, during binding, sess points to the target session looked up via ksmbd_session_lookup_slowpath() -- which belongs to another connection's user. This allows a remote attacker to invalidate any active session by simply sending a binding request with a wrong password (DoS). Fix this by skipping session expiration when the failed request was a binding attempt, since the session does not belong to the current connection. The reference taken by ksmbd_session_lookup_slowpath() is still correctly released via ksmbd_user_session_put().

Severity

8.2 (High)


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

Assigner

Linux mitre root

References

7 references

URL	Tags
https://git.kernel.org/stable/c/4642ea35c03cf3d35…
https://git.kernel.org/stable/c/f5300690c23c5ac86…
https://git.kernel.org/stable/c/6fafc4c4238e53896…
https://git.kernel.org/stable/c/1d1888b4a7aec518b…
https://git.kernel.org/stable/c/a897064a457056acb…
https://git.kernel.org/stable/c/e0e5edc81b241c703…
https://git.kernel.org/stable/c/9bbb19d21ded7d786…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: f5a544e3bab78142207e0242d22442db85ba1eff , < 4642ea35c03cf3d3558c009df4757cdb7af3f82d (git) Affected: f5a544e3bab78142207e0242d22442db85ba1eff , < f5300690c23c5ac860499bb37dbc09cf43fd62e6 (git) Affected: f5a544e3bab78142207e0242d22442db85ba1eff , < 6fafc4c4238e538969f1375f9ecdc6587c53f1cc (git) Affected: f5a544e3bab78142207e0242d22442db85ba1eff , < 1d1888b4a7aec518b707f6eca0bf08992c0e8da3 (git) Affected: f5a544e3bab78142207e0242d22442db85ba1eff , < a897064a457056acb976e20e3007cdf553de340f (git) Affected: f5a544e3bab78142207e0242d22442db85ba1eff , < e0e5edc81b241c70355217de7e120c97c3429deb (git) Affected: f5a544e3bab78142207e0242d22442db85ba1eff , < 9bbb19d21ded7d78645506f20d8c44895e3d0fb9 (git)
Linux	Linux	Affected: 5.15 Unaffected: 0 , < 5.15 (semver) Unaffected: 5.15.209 , ≤ 5.15.* (semver) Unaffected: 6.1.168 , ≤ 6.1.* (semver) Unaffected: 6.6.131 , ≤ 6.6.* (semver) Unaffected: 6.12.80 , ≤ 6.12.* (semver) Unaffected: 6.18.21 , ≤ 6.18.* (semver) Unaffected: 6.19.11 , ≤ 6.19.* (semver) Unaffected: 7.0 , ≤ * (original_commit_for_fix)

Show details on NVD website

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{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/smb/server/smb2pdu.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "4642ea35c03cf3d3558c009df4757cdb7af3f82d",
              "status": "affected",
              "version": "f5a544e3bab78142207e0242d22442db85ba1eff",
              "versionType": "git"
            },
            {
              "lessThan": "f5300690c23c5ac860499bb37dbc09cf43fd62e6",
              "status": "affected",
              "version": "f5a544e3bab78142207e0242d22442db85ba1eff",
              "versionType": "git"
            },
            {
              "lessThan": "6fafc4c4238e538969f1375f9ecdc6587c53f1cc",
              "status": "affected",
              "version": "f5a544e3bab78142207e0242d22442db85ba1eff",
              "versionType": "git"
            },
            {
              "lessThan": "1d1888b4a7aec518b707f6eca0bf08992c0e8da3",
              "status": "affected",
              "version": "f5a544e3bab78142207e0242d22442db85ba1eff",
              "versionType": "git"
            },
            {
              "lessThan": "a897064a457056acb976e20e3007cdf553de340f",
              "status": "affected",
              "version": "f5a544e3bab78142207e0242d22442db85ba1eff",
              "versionType": "git"
            },
            {
              "lessThan": "e0e5edc81b241c70355217de7e120c97c3429deb",
              "status": "affected",
              "version": "f5a544e3bab78142207e0242d22442db85ba1eff",
              "versionType": "git"
            },
            {
              "lessThan": "9bbb19d21ded7d78645506f20d8c44895e3d0fb9",
              "status": "affected",
              "version": "f5a544e3bab78142207e0242d22442db85ba1eff",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/smb/server/smb2pdu.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.15"
            },
            {
              "lessThan": "5.15",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.209",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.168",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.131",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.80",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.21",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.19.*",
              "status": "unaffected",
              "version": "6.19.11",
              "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": "5.15.209",
                  "versionStartIncluding": "5.15",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.1.168",
                  "versionStartIncluding": "5.15",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.131",
                  "versionStartIncluding": "5.15",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.80",
                  "versionStartIncluding": "5.15",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.21",
                  "versionStartIncluding": "5.15",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.19.11",
                  "versionStartIncluding": "5.15",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.0",
                  "versionStartIncluding": "5.15",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: do not expire session on binding failure\n\nWhen a multichannel session binding request fails (e.g. wrong password),\nthe error path unconditionally sets sess-\u003estate = SMB2_SESSION_EXPIRED.\nHowever, during binding, sess points to the target session looked up via\nksmbd_session_lookup_slowpath() -- which belongs to another connection\u0027s\nuser. This allows a remote attacker to invalidate any active session by\nsimply sending a binding request with a wrong password (DoS).\n\nFix this by skipping session expiration when the failed request was\na binding attempt, since the session does not belong to the current\nconnection. The reference taken by ksmbd_session_lookup_slowpath() is\nstill correctly released via ksmbd_user_session_put()."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 8.2,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:N - ksmbd is an in-kernel SMB server reachable over TCP, commonly on port 445, and the vulnerable path is reached by remote SMB2 SESSION_SETUP traffic. The binding failure is processed from network-supplied SMB packets.\nAC:L - With SMB3 multichannel enabled and an active target session, the attacker can trigger the flaw by sending a binding SESSION_SETUP request that fails authentication. There is no race or memory-layout dependency, and uncertainty about required protocol identifiers is resolved toward the higher-severity low-complexity value.\nPR:N - SMB2 SESSION_SETUP is explicitly exempt from the normal authenticated session check, and the bug is triggered on the failed authentication path before attacker credentials are accepted. The code checks the signed flag but does not cryptographically validate the binding request before expiring the looked-up session.\nUI:N - The attacker sends network SMB requests directly to the ksmbd service. No victim action is required during exploitation beyond the existence of an active SMB session to disrupt.\nS:U - The impact remains within the same kernel/ksmbd server security authority. It does not cross a VM, sandbox, IOMMU, or other separate authorization boundary.\nC:N - The bug changes session state but does not expose memory, file contents, credentials, or other confidential data. No information disclosure primitive was found.\nI:L - The attacker can cause an unauthorized change to a security-relevant server-side session object by forcing another session into SMB2_SESSION_EXPIRED. This is limited state modification, not arbitrary write or code execution.\nA:H - The vulnerable code invalidates active SMB sessions belonging to other connections, disrupting their file/service access. Repeating the unauthenticated network trigger can deny ksmbd service availability to active clients."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T12:22:55.000Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/4642ea35c03cf3d3558c009df4757cdb7af3f82d"
        },
        {
          "url": "https://git.kernel.org/stable/c/f5300690c23c5ac860499bb37dbc09cf43fd62e6"
        },
        {
          "url": "https://git.kernel.org/stable/c/6fafc4c4238e538969f1375f9ecdc6587c53f1cc"
        },
        {
          "url": "https://git.kernel.org/stable/c/1d1888b4a7aec518b707f6eca0bf08992c0e8da3"
        },
        {
          "url": "https://git.kernel.org/stable/c/a897064a457056acb976e20e3007cdf553de340f"
        },
        {
          "url": "https://git.kernel.org/stable/c/e0e5edc81b241c70355217de7e120c97c3429deb"
        },
        {
          "url": "https://git.kernel.org/stable/c/9bbb19d21ded7d78645506f20d8c44895e3d0fb9"
        }
      ],
      "title": "ksmbd: do not expire session on binding failure",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-31476",
    "datePublished": "2026-04-22T13:54:04.779Z",
    "dateReserved": "2026-03-09T15:48:24.098Z",
    "dateUpdated": "2026-08-05T12:22:55.000Z",
    "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.

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.

Action not permitted

BDU:2026-12527 (CVE-2026-31476)

CVE-2026-31476 (GCVE-0-2026-31476)

Tags

Sightings

Nomenclature

Related by attack behaviour