Vulnerability-Lookup

BDU:2026-02230 (CVE-2025-21967)

Vulnerability from fstec – Published: 2026-02-25 – Updated: 2026-02-25 – View on bdu.fstec.ru Fixed

Title

Уязвимость функции ksmbd_alloc_work_struct() модуля fs/smb/server/ksmbd_work.c поддержки сервера SMB ядра операционной системы Linux, позволяющая нарушителю оказать воздействие на конфиденциальность, целостность и доступность защищаемой информации

Summary

Уязвимость функции ksmbd_alloc_work_struct() модуля fs/smb/server/ksmbd_work.c поддержки сервера SMB 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

6.8 (Medium) CVSS 2.0


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

7.8 (High) CVSS 3.1


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

Class

Code vulnerability

Status

Confirmed by the vendor

Exploitation

Data structure manipulation

Incidents

Being clarified

Remediation

Software update

CWE

CWE-416 - Использование после освобождения

Aliases

CVE-2025-21967

References

29 references

URL
https://git.kernel.org/stable/c/eb51f6f59d19b92f6fe84d3873f958495ab32f0a
https://git.kernel.org/stable/c/62746ae3f5414244a96293e3b017be637b641280
https://git.kernel.org/stable/c/fb776765bfc21d5e4ed03bb3d4406c2b86ff1ac3
https://www.cve.org/CVERecord?id=CVE-2025-21967
https://lore.kernel.org/linux-cve-announce/2025040146-CVE-2025-21967-114e@gregkh/
https://git.kernel.org/linus/bb39ed47065455604729404729d9116868638d31
https://ubuntu.com/security/notices/USN-7605-1
https://ubuntu.com/security/notices/USN-7606-1
https://ubuntu.com/security/notices/USN-7605-2
https://ubuntu.com/security/notices/USN-7628-1
https://ubuntu.com/security/notices/USN-7764-1
https://ubuntu.com/security/notices/USN-7765-1
https://ubuntu.com/security/notices/USN-7766-1
https://ubuntu.com/security/notices/USN-7767-1
https://ubuntu.com/security/notices/USN-7779-1
https://ubuntu.com/security/notices/USN-7767-2
https://ubuntu.com/security/notices/USN-7764-2
https://ubuntu.com/security/notices/USN-7790-1
https://ubuntu.com/security/notices/USN-7800-1
https://ubuntu.com/security/notices/USN-7801-1
https://ubuntu.com/security/notices/USN-7802-1
https://ubuntu.com/security/notices/USN-7801-2
https://ubuntu.com/security/notices/USN-7809-1
https://ubuntu.com/security/notices/USN-7801-3
https://kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.6.84
https://kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.12.20
https://kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.13.8
https://security-tracker.debian.org/tracker/CVE-2025-21967
https://ubuntu.com/security/CVE-2025-21967

Impacted products

3 products from 2 vendors

Vendors

Canonical Ltd., Сообщество свободного программного обеспечения

Products

Ubuntu, Debian GNU/Linux, Linux

Versions

16.04 LTS (Ubuntu), 18.04 LTS (Ubuntu), 20.04 LTS (Ubuntu), 12 (Debian GNU/Linux), 22.04 LTS (Ubuntu), 13 (Debian GNU/Linux), от 5.15 до 6.6.83 включительно (Linux), от 6.7 до 6.12.19 включительно (Linux), от 6.13 до 6.13.7 включительно (Linux)

Product types

Operating system

Platforms

Canonical Ltd. Ubuntu 16.04 LTS, Canonical Ltd. Ubuntu 18.04 LTS, Canonical Ltd. Ubuntu 20.04 LTS, Сообщество свободного программного обеспечения Debian GNU/Linux 12, Canonical Ltd. Ubuntu 22.04 LTS, Сообщество свободного программного обеспечения Debian GNU/Linux 13, Сообщество свободного программного обеспечения Linux от 5.15 до 6.6.83 включительно, Сообщество свободного программного обеспечения Linux от 6.7 до 6.12.19 включительно, Сообщество свободного программного обеспечения Linux от 6.13 до 6.13.7 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/eb51f6f59d19b92f6fe84d3873f958495ab32f0a https://git.kernel.org/stable/c/62746ae3f5414244a96293e3b017be637b641280 https://git.kernel.org/stable/c/fb776765bfc21d5e4ed03bb3d4406c2b86ff1ac3 https://lore.kernel.org/linux-cve-announce/2025040146-CVE-2025-21967-114e@gregkh/ https://git.kernel.org/linus/bb39ed47065455604729404729d9116868638d31 Для Debian GNU/Linux: https://security-tracker.debian.org/tracker/CVE-2025-21967 Для Ubuntu: https://ubuntu.com/security/CVE-2025-21967

JSON

To clipboard

{
  "CVSS 2.0": "AV:L/AC:L/Au:S/C:C/I:C/A:C",
  "CVSS 3.0": "AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
  "CVSS 4.0": null,
  "remediation_\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440": null,
  "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",
  "\u0412\u0435\u0440\u0441\u0438\u044f \u041f\u041e": "16.04 LTS (Ubuntu), 18.04 LTS (Ubuntu), 20.04 LTS (Ubuntu), 12 (Debian GNU/Linux), 22.04 LTS (Ubuntu), 13 (Debian GNU/Linux), \u043e\u0442 5.15 \u0434\u043e 6.6.83 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e (Linux), \u043e\u0442 6.7 \u0434\u043e 6.12.19 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e (Linux), \u043e\u0442 6.13 \u0434\u043e 6.13.7 \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://git.kernel.org/stable/c/eb51f6f59d19b92f6fe84d3873f958495ab32f0a\nhttps://git.kernel.org/stable/c/62746ae3f5414244a96293e3b017be637b641280\nhttps://git.kernel.org/stable/c/fb776765bfc21d5e4ed03bb3d4406c2b86ff1ac3\nhttps://lore.kernel.org/linux-cve-announce/2025040146-CVE-2025-21967-114e@gregkh/\nhttps://git.kernel.org/linus/bb39ed47065455604729404729d9116868638d31\n\n\u0414\u043b\u044f Debian GNU/Linux:\nhttps://security-tracker.debian.org/tracker/CVE-2025-21967\n\n\u0414\u043b\u044f Ubuntu:\nhttps://ubuntu.com/security/CVE-2025-21967",
  "\u0414\u0430\u0442\u0430 \u0432\u044b\u044f\u0432\u043b\u0435\u043d\u0438\u044f": "10.03.2025",
  "\u0414\u0430\u0442\u0430 \u043f\u043e\u0441\u043b\u0435\u0434\u043d\u0435\u0433\u043e \u043e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u044f": "25.02.2026",
  "\u0414\u0430\u0442\u0430 \u043f\u0443\u0431\u043b\u0438\u043a\u0430\u0446\u0438\u0438": "25.02.2026",
  "\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440": "BDU:2026-02230",
  "\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440\u044b \u0434\u0440\u0443\u0433\u0438\u0445 \u0441\u0438\u0441\u0442\u0435\u043c \u043e\u043f\u0438\u0441\u0430\u043d\u0438\u0439 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "CVE-2025-21967",
  "\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": "Ubuntu, Debian GNU/Linux, 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 16.04 LTS , Canonical Ltd. Ubuntu 18.04 LTS , 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 12 , Canonical Ltd. Ubuntu 22.04 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 5.15 \u0434\u043e 6.6.83 \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 6.12.19 \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 6.13.7 \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 ksmbd_alloc_work_struct() \u043c\u043e\u0434\u0443\u043b\u044f fs/smb/server/ksmbd_work.c \u043f\u043e\u0434\u0434\u0435\u0440\u0436\u043a\u0438 \u0441\u0435\u0440\u0432\u0435\u0440\u0430 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 \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\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 ksmbd_alloc_work_struct() \u043c\u043e\u0434\u0443\u043b\u044f fs/smb/server/ksmbd_work.c \u043f\u043e\u0434\u0434\u0435\u0440\u0436\u043a\u0438 \u0441\u0435\u0440\u0432\u0435\u0440\u0430 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 \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",
  "\u0421\u0441\u044b\u043b\u043a\u0438 \u043d\u0430 \u0438\u0441\u0442\u043e\u0447\u043d\u0438\u043a\u0438": "https://git.kernel.org/stable/c/eb51f6f59d19b92f6fe84d3873f958495ab32f0a\nhttps://git.kernel.org/stable/c/62746ae3f5414244a96293e3b017be637b641280\nhttps://git.kernel.org/stable/c/fb776765bfc21d5e4ed03bb3d4406c2b86ff1ac3\nhttps://www.cve.org/CVERecord?id=CVE-2025-21967\nhttps://lore.kernel.org/linux-cve-announce/2025040146-CVE-2025-21967-114e@gregkh/\nhttps://git.kernel.org/linus/bb39ed47065455604729404729d9116868638d31\nhttps://ubuntu.com/security/notices/USN-7605-1\nhttps://ubuntu.com/security/notices/USN-7606-1\nhttps://ubuntu.com/security/notices/USN-7605-2\nhttps://ubuntu.com/security/notices/USN-7628-1\nhttps://ubuntu.com/security/notices/USN-7764-1\nhttps://ubuntu.com/security/notices/USN-7765-1\nhttps://ubuntu.com/security/notices/USN-7766-1\nhttps://ubuntu.com/security/notices/USN-7767-1\nhttps://ubuntu.com/security/notices/USN-7779-1\nhttps://ubuntu.com/security/notices/USN-7767-2\nhttps://ubuntu.com/security/notices/USN-7764-2\nhttps://ubuntu.com/security/notices/USN-7790-1\nhttps://ubuntu.com/security/notices/USN-7800-1\nhttps://ubuntu.com/security/notices/USN-7801-1\nhttps://ubuntu.com/security/notices/USN-7802-1\nhttps://ubuntu.com/security/notices/USN-7801-2\nhttps://ubuntu.com/security/notices/USN-7809-1\nhttps://ubuntu.com/security/notices/USN-7801-3\nhttps://kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.6.84\nhttps://kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.12.20\nhttps://kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.13.8\nhttps://security-tracker.debian.org/tracker/CVE-2025-21967\nhttps://ubuntu.com/security/CVE-2025-21967",
  "\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",
  "\u0423\u0440\u043e\u0432\u0435\u043d\u044c \u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u0421\u0440\u0435\u0434\u043d\u0438\u0439 \u0443\u0440\u043e\u0432\u0435\u043d\u044c \u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438 (\u0431\u0430\u0437\u043e\u0432\u0430\u044f \u043e\u0446\u0435\u043d\u043a\u0430 CVSS 2.0 \u0441\u043e\u0441\u0442\u0430\u0432\u043b\u044f\u0435\u0442 6,8)\n\u0412\u044b\u0441\u043e\u043a\u0438\u0439 \u0443\u0440\u043e\u0432\u0435\u043d\u044c \u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438 (\u0431\u0430\u0437\u043e\u0432\u0430\u044f \u043e\u0446\u0435\u043d\u043a\u0430 CVSS 3.1 \u0441\u043e\u0441\u0442\u0430\u0432\u043b\u044f\u0435\u0442 7,8)"
}

CVE-2025-21967 (GCVE-0-2025-21967)

Vulnerability from cvelistv5 – Published: 2025-04-01 15:47 – Updated: 2026-08-05 11:55

Title

ksmbd: fix use-after-free in ksmbd_free_work_struct

Summary

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix use-after-free in ksmbd_free_work_struct ->interim_entry of ksmbd_work could be deleted after oplock is freed. We don't need to manage it with linked list. The interim request could be immediately sent whenever a oplock break wait is needed.

Severity

8.8 (High)


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

7.8 (High)


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

SSVC

Exploitation: none Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2025-04-16 13:14 UTC

CWE

CWE-416 - Use After Free

Assigner

Linux mitre root

References

4 references

URL	Tags
https://git.kernel.org/stable/c/fb776765bfc21d5e4…
https://git.kernel.org/stable/c/62746ae3f5414244a…
https://git.kernel.org/stable/c/eb51f6f59d19b92f6…
https://git.kernel.org/stable/c/bb39ed47065455604…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < fb776765bfc21d5e4ed03bb3d4406c2b86ff1ac3 (git) Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < 62746ae3f5414244a96293e3b017be637b641280 (git) Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < eb51f6f59d19b92f6fe84d3873f958495ab32f0a (git) Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < bb39ed47065455604729404729d9116868638d31 (git)
Linux	Linux	Affected: 5.15 Unaffected: 0 , < 5.15 (semver) Unaffected: 6.6.84 , ≤ 6.6.* (semver) Unaffected: 6.12.20 , ≤ 6.12.* (semver) Unaffected: 6.13.8 , ≤ 6.13.* (semver) Unaffected: 6.14 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "cvssV3_1": {
              "attackComplexity": "LOW",
              "attackVector": "LOCAL",
              "availabilityImpact": "HIGH",
              "baseScore": 7.8,
              "baseSeverity": "HIGH",
              "confidentialityImpact": "HIGH",
              "integrityImpact": "HIGH",
              "privilegesRequired": "LOW",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
              "version": "3.1"
            }
          },
          {
            "other": {
              "content": {
                "id": "CVE-2025-21967",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2025-04-16T13:14:51.011092Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "problemTypes": [
          {
            "descriptions": [
              {
                "cweId": "CWE-416",
                "description": "CWE-416 Use After Free",
                "lang": "en",
                "type": "CWE"
              }
            ]
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2025-04-16T13:19:52.457Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/smb/server/ksmbd_work.c",
            "fs/smb/server/ksmbd_work.h",
            "fs/smb/server/oplock.c",
            "fs/smb/server/oplock.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "fb776765bfc21d5e4ed03bb3d4406c2b86ff1ac3",
              "status": "affected",
              "version": "0626e6641f6b467447c81dd7678a69c66f7746cf",
              "versionType": "git"
            },
            {
              "lessThan": "62746ae3f5414244a96293e3b017be637b641280",
              "status": "affected",
              "version": "0626e6641f6b467447c81dd7678a69c66f7746cf",
              "versionType": "git"
            },
            {
              "lessThan": "eb51f6f59d19b92f6fe84d3873f958495ab32f0a",
              "status": "affected",
              "version": "0626e6641f6b467447c81dd7678a69c66f7746cf",
              "versionType": "git"
            },
            {
              "lessThan": "bb39ed47065455604729404729d9116868638d31",
              "status": "affected",
              "version": "0626e6641f6b467447c81dd7678a69c66f7746cf",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/smb/server/ksmbd_work.c",
            "fs/smb/server/ksmbd_work.h",
            "fs/smb/server/oplock.c",
            "fs/smb/server/oplock.h"
          ],
          "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": "6.6.*",
              "status": "unaffected",
              "version": "6.6.84",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.20",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.13.*",
              "status": "unaffected",
              "version": "6.13.8",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.14",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.84",
                  "versionStartIncluding": "5.15",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.20",
                  "versionStartIncluding": "5.15",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.13.8",
                  "versionStartIncluding": "5.15",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.14",
                  "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: fix use-after-free in ksmbd_free_work_struct\n\n-\u003einterim_entry of ksmbd_work could be deleted after oplock is freed.\nWe don\u0027t need to manage it with linked list. The interim request could be\nimmediately sent whenever a oplock break wait is needed."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 8.8,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:N - ksmbd is the in-kernel SMB server listening on TCP/445, and the entire trigger sequence (a CREATE requesting a batch oplock/write lease on one connection, a conflicting overwrite CREATE plus a close/disconnect on a second) is driven purely by remote SMB2 protocol traffic. No local access to the target is required.\nAC:L - The double `list_add` of the same `work-\u003einterim_entry` in `smb2_open()` is deterministic, not racy, and the attacker owns both connections so it chooses exactly when the peer\u0027s `oplock_info` is released relative to `ksmbd_free_work_struct()`, and can loop the sequence indefinitely. Per guidance, an attacker-created ordering and a use-after-free are Low.\nPR:L - Reaching `smb_grant_oplock()`/`smb_break_all_oplock()` requires a completed SESSION_SETUP, TREE_CONNECT and SMB2 CREATE, so an authenticated but otherwise unprivileged share account (including a mapped guest) is needed. This matches the scoring of the sibling post-authentication ksmbd oplock UAFs.\nUI:N - The attacker drives every step from its own two SMB sessions \u2014 take the oplock, issue the conflicting overwrite CREATE, then close or drop the first connection. No administrator or other client has to do anything.\nS:U - The list corruption and its consequences stay entirely within the kernel\u0027s own security authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - The stale `interim_list` head lets `smb2_lease_break_noti()` treat reclaimed heap memory as a `struct ksmbd_work`, dereferencing its `conn`, `sess`, and `request_buf` fields, and `smb2_send_interim_resp()` then transmits data derived from that object back to the attacker \u2014 an arbitrary kernel memory disclosure primitive after a heap spray.\nI:H - `list_del()` in `ksmbd_free_work_struct()` writes two attacker-influenced kernel heap pointers at a fixed offset into a freed kmalloc-256 slot that the attacker can reclaim with a chosen object, and the fake-`ksmbd_work` path yields further controlled pointer writes and indirect calls, giving control-flow hijack.\nA:H - Even unweaponized, the `list_del` on freed memory trips `CONFIG_DEBUG_LIST`/`BUG()` or silently corrupts the slab, and walking the dangling `interim_list` oopses the ksmbd worker; the attacker can repeat it at will to keep the file server down."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T11:55:43.302Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/fb776765bfc21d5e4ed03bb3d4406c2b86ff1ac3"
        },
        {
          "url": "https://git.kernel.org/stable/c/62746ae3f5414244a96293e3b017be637b641280"
        },
        {
          "url": "https://git.kernel.org/stable/c/eb51f6f59d19b92f6fe84d3873f958495ab32f0a"
        },
        {
          "url": "https://git.kernel.org/stable/c/bb39ed47065455604729404729d9116868638d31"
        }
      ],
      "title": "ksmbd: fix use-after-free in ksmbd_free_work_struct",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2025-21967",
    "datePublished": "2025-04-01T15:47:02.364Z",
    "dateReserved": "2024-12-29T08:45:45.796Z",
    "dateUpdated": "2026-08-05T11:55:43.302Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

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

Detection rules are retrieved from Rulezet.

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

Related by attack behaviour

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