Vulnerability-Lookup

BDU:2025-12056 (CVE-2025-21766)

Vulnerability from fstec – Published: 2025-09-28 – Updated: 2026-07-07 – View on bdu.fstec.ru Fixed

Title

Уязвимость функции __ip_rt_update_pmtu() компонента ipv4/route.c ядра операционной системы Linux, позволяющая нарушителю вызвать отказ в обслуживании

Summary

Уязвимость функции __ip_rt_update_pmtu() компонента ipv4/route.c ядра операционной системы Linux связана с неправильной блокировкой ресурсов. 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-413 - Неправильное блокирование ресурсов

Aliases

CVE-2025-21766

References

14 references

URL
https://git.kernel.org/linus/139512191bd06f1b496117c76372b2ce372c9a41
https://git.kernel.org/stable/c/139512191bd06f1b496117c76372b2ce372c9a41
https://git.kernel.org/stable/c/4583748b65dee4d61bd50a2214715b4237bc152a
https://git.kernel.org/stable/c/9b1766d1ff5fe496aabe9fc5f4e34e53f35c11c4
https://git.kernel.org/stable/c/a39f61d212d822b3062d7f70fa0588e50e55664e
https://git.kernel.org/stable/c/ce3c6165fce0f06305c806696882a3ad4b90e33f
https://git.kernel.org/stable/c/ea07480b23225942208f1b754fea1e7ec486d37e
https://github.com/torvalds/linux/commit/139512191bd06f1b496117c76372b2ce372c9a41
https://nvd.nist.gov/vuln/detail/CVE-2025-21766
https://security-tracker.debian.org/tracker/CVE-2025-21766
https://wiki.astralinux.ru/astra-linux-se18-bulletin-2025-0811SE18
https://поддержка.нппкт.рф/bin/view/ОСнова/Обновления/2.13/
https://abf.rosa.ru/advisories/ROSA-SA-2026-3261
https://abf.rosa.ru/advisories/ROSA-SA-2026-3262

Impacted products

5 products from 4 vendors

Vendors

АО «НТЦ ИТ РОСА», Сообщество свободного программного обеспечения, ООО «РусБИТех-Астра», АО «НППКТ»

Products

ROSA Virtualization (запись в едином реестре российских программ №5091), Linux, Astra Linux Special Edition (запись в едином реестре российских программ №369), ROSA Virtualization 3.0 (запись в едином реестре российских программ №21308), ОСОН ОСнова Оnyx (запись в едином реестре российских программ №5913)

Versions

2.1 (ROSA Virtualization), от 4.14.200 до 4.15 (Linux), от 4.19.148 до 4.20 (Linux), 1.8 (Astra Linux Special Edition), 3.0 (ROSA Virtualization 3.0), до 2.13 (ОСОН ОСнова Оnyx), от 5.16 до 6.1.129 (Linux), от 6.13 до 6.13.4 (Linux), от 6.7 до 6.12.16 (Linux), от 6.2 до 6.6.79 (Linux), от 5.4.68 до 5.5 (Linux), от 5.8.12 до 5.15.179 (Linux)

Product types

Virtualization software, Operating system

Platforms

АО «НТЦ ИТ РОСА» ROSA Virtualization 2.1 (запись в едином реестре российских программ №5091), Сообщество свободного программного обеспечения Linux от 4.14.200 до 4.15, Сообщество свободного программного обеспечения Linux от 4.19.148 до 4.20, ООО «РусБИТех-Астра» Astra Linux Special Edition 1.8 (запись в едином реестре российских программ №369), АО «НТЦ ИТ РОСА» ROSA Virtualization 3.0 3.0 (запись в едином реестре российских программ №21308), АО «НППКТ» ОСОН ОСнова Оnyx до 2.13 (запись в едином реестре российских программ №5913), Сообщество свободного программного обеспечения Linux от 5.16 до 6.1.129, Сообщество свободного программного обеспечения Linux от 6.13 до 6.13.4, Сообщество свободного программного обеспечения Linux от 6.7 до 6.12.16, Сообщество свободного программного обеспечения Linux от 6.2 до 6.6.79, Сообщество свободного программного обеспечения Linux от 5.4.68 до 5.5, Сообщество свободного программного обеспечения Linux от 5.8.12 до 5.15.179

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://github.com/torvalds/linux/commit/139512191bd06f1b496117c76372b2ce372c9a41 Для ОС Astra Linux: - обновить пакет linux-6.1 до 6.1.141-1.astra1+ci6 или более высокой версии, используя рекомендации производителя: https://wiki.astralinux.ru/astra-linux-se18-bulletin-2025-0811SE18 - обновить пакет linux-6.12 до 6.12.34-1.astra1+ci2 или более высокой версии, используя рекомендации производителя: https://wiki.astralinux.ru/astra-linux-se18-bulletin-2025-0811SE18 Обновление программного обеспечения linux до версии 6.6.90-0.osnova2u1 Для системы управления средой виртуализации «ROSA Virtualization»: https://abf.rosa.ru/advisories/ROSA-SA-2026-3261 Для программной системы управления средой виртуализации с подсистемой безагентного резервного копирования виртуальных машин «ROSA Virtualization 3.0»: https://abf.rosa.ru/advisories/ROSA-SA-2026-3262

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,
  "remediation_\u041d\u0430\u0438\u043c\u0435\u043d\u043e\u0432\u0430\u043d\u0438\u0435": null,
  "\u0412\u0435\u043d\u0434\u043e\u0440 \u041f\u041e": "\u0410\u041e \u00ab\u041d\u0422\u0426 \u0418\u0422 \u0420\u041e\u0421\u0410\u00bb, \u0421\u043e\u043e\u0431\u0449\u0435\u0441\u0442\u0432\u043e \u0441\u0432\u043e\u0431\u043e\u0434\u043d\u043e\u0433\u043e \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f, \u041e\u041e\u041e \u00ab\u0420\u0443\u0441\u0411\u0418\u0422\u0435\u0445-\u0410\u0441\u0442\u0440\u0430\u00bb, \u0410\u041e \u00ab\u041d\u041f\u041f\u041a\u0422\u00bb",
  "\u0412\u0435\u0440\u0441\u0438\u044f \u041f\u041e": "2.1 (ROSA Virtualization), \u043e\u0442 4.14.200 \u0434\u043e 4.15 (Linux), \u043e\u0442 4.19.148 \u0434\u043e 4.20 (Linux), 1.8 (Astra Linux Special Edition), 3.0 (ROSA Virtualization 3.0), \u0434\u043e 2.13 (\u041e\u0421\u041e\u041d \u041e\u0421\u043d\u043e\u0432\u0430 \u041enyx), \u043e\u0442 5.16 \u0434\u043e 6.1.129 (Linux), \u043e\u0442 6.13 \u0434\u043e 6.13.4 (Linux), \u043e\u0442 6.7 \u0434\u043e 6.12.16 (Linux), \u043e\u0442 6.2 \u0434\u043e 6.6.79 (Linux), \u043e\u0442 5.4.68 \u0434\u043e 5.5 (Linux), \u043e\u0442 5.8.12 \u0434\u043e 5.15.179 (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://github.com/torvalds/linux/commit/139512191bd06f1b496117c76372b2ce372c9a41\n\n\u0414\u043b\u044f \u041e\u0421 Astra Linux:\n- \u043e\u0431\u043d\u043e\u0432\u0438\u0442\u044c \u043f\u0430\u043a\u0435\u0442 linux-6.1 \u0434\u043e 6.1.141-1.astra1+ci6 \u0438\u043b\u0438 \u0431\u043e\u043b\u0435\u0435 \u0432\u044b\u0441\u043e\u043a\u043e\u0439 \u0432\u0435\u0440\u0441\u0438\u0438, \u0438\u0441\u043f\u043e\u043b\u044c\u0437\u0443\u044f \u0440\u0435\u043a\u043e\u043c\u0435\u043d\u0434\u0430\u0446\u0438\u0438 \u043f\u0440\u043e\u0438\u0437\u0432\u043e\u0434\u0438\u0442\u0435\u043b\u044f: https://wiki.astralinux.ru/astra-linux-se18-bulletin-2025-0811SE18\n- \u043e\u0431\u043d\u043e\u0432\u0438\u0442\u044c \u043f\u0430\u043a\u0435\u0442 linux-6.12 \u0434\u043e 6.12.34-1.astra1+ci2 \u0438\u043b\u0438 \u0431\u043e\u043b\u0435\u0435 \u0432\u044b\u0441\u043e\u043a\u043e\u0439 \u0432\u0435\u0440\u0441\u0438\u0438, \u0438\u0441\u043f\u043e\u043b\u044c\u0437\u0443\u044f \u0440\u0435\u043a\u043e\u043c\u0435\u043d\u0434\u0430\u0446\u0438\u0438 \u043f\u0440\u043e\u0438\u0437\u0432\u043e\u0434\u0438\u0442\u0435\u043b\u044f: https://wiki.astralinux.ru/astra-linux-se18-bulletin-2025-0811SE18\n\n\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 linux \u0434\u043e \u0432\u0435\u0440\u0441\u0438\u0438 6.6.90-0.osnova2u1\n\n\u0414\u043b\u044f \u0441\u0438\u0441\u0442\u0435\u043c\u044b \u0443\u043f\u0440\u0430\u0432\u043b\u0435\u043d\u0438\u044f \u0441\u0440\u0435\u0434\u043e\u0439 \u0432\u0438\u0440\u0442\u0443\u0430\u043b\u0438\u0437\u0430\u0446\u0438\u0438 \u00abROSA Virtualization\u00bb: https://abf.rosa.ru/advisories/ROSA-SA-2026-3261\n\n\u0414\u043b\u044f \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0439 \u0441\u0438\u0441\u0442\u0435\u043c\u044b \u0443\u043f\u0440\u0430\u0432\u043b\u0435\u043d\u0438\u044f \u0441\u0440\u0435\u0434\u043e\u0439 \u0432\u0438\u0440\u0442\u0443\u0430\u043b\u0438\u0437\u0430\u0446\u0438\u0438 \u0441 \u043f\u043e\u0434\u0441\u0438\u0441\u0442\u0435\u043c\u043e\u0439 \u0431\u0435\u0437\u0430\u0433\u0435\u043d\u0442\u043d\u043e\u0433\u043e \u0440\u0435\u0437\u0435\u0440\u0432\u043d\u043e\u0433\u043e \u043a\u043e\u043f\u0438\u0440\u043e\u0432\u0430\u043d\u0438\u044f \u0432\u0438\u0440\u0442\u0443\u0430\u043b\u044c\u043d\u044b\u0445 \u043c\u0430\u0448\u0438\u043d \u00abROSA Virtualization 3.0\u00bb: https://abf.rosa.ru/advisories/ROSA-SA-2026-3262",
  "\u0414\u0430\u0442\u0430 \u0432\u044b\u044f\u0432\u043b\u0435\u043d\u0438\u044f": "07.02.2025",
  "\u0414\u0430\u0442\u0430 \u043f\u043e\u0441\u043b\u0435\u0434\u043d\u0435\u0433\u043e \u043e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u044f": "07.07.2026",
  "\u0414\u0430\u0442\u0430 \u043f\u0443\u0431\u043b\u0438\u043a\u0430\u0446\u0438\u0438": "28.09.2025",
  "\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440": "BDU:2025-12056",
  "\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-2025-21766",
  "\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": "ROSA Virtualization (\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 \u21165091), Linux, Astra Linux Special Edition (\u0437\u0430\u043f\u0438\u0441\u044c \u0432 \u0435\u0434\u0438\u043d\u043e\u043c \u0440\u0435\u0435\u0441\u0442\u0440\u0435 \u0440\u043e\u0441\u0441\u0438\u0439\u0441\u043a\u0438\u0445 \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c \u2116369), ROSA Virtualization 3.0 (\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 \u211621308), \u041e\u0421\u041e\u041d \u041e\u0421\u043d\u043e\u0432\u0430 \u041enyx (\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 \u21165913)",
  "\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": "\u0410\u041e \u00ab\u041d\u0422\u0426 \u0418\u0422 \u0420\u041e\u0421\u0410\u00bb ROSA Virtualization 2.1  (\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 \u21165091), \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 4.14.200 \u0434\u043e 4.15 , \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 4.19.148 \u0434\u043e 4.20 , \u041e\u041e\u041e \u00ab\u0420\u0443\u0441\u0411\u0418\u0422\u0435\u0445-\u0410\u0441\u0442\u0440\u0430\u00bb Astra Linux Special Edition 1.8  (\u0437\u0430\u043f\u0438\u0441\u044c \u0432 \u0435\u0434\u0438\u043d\u043e\u043c \u0440\u0435\u0435\u0441\u0442\u0440\u0435 \u0440\u043e\u0441\u0441\u0438\u0439\u0441\u043a\u0438\u0445 \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c \u2116369), \u0410\u041e \u00ab\u041d\u0422\u0426 \u0418\u0422 \u0420\u041e\u0421\u0410\u00bb ROSA Virtualization 3.0 3.0  (\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 \u211621308), \u0410\u041e \u00ab\u041d\u041f\u041f\u041a\u0422\u00bb \u041e\u0421\u041e\u041d \u041e\u0421\u043d\u043e\u0432\u0430 \u041enyx \u0434\u043e 2.13  (\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 \u21165913), \u0421\u043e\u043e\u0431\u0449\u0435\u0441\u0442\u0432\u043e \u0441\u0432\u043e\u0431\u043e\u0434\u043d\u043e\u0433\u043e \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f Linux \u043e\u0442 5.16 \u0434\u043e 6.1.129 , \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 6.13.4 , \u0421\u043e\u043e\u0431\u0449\u0435\u0441\u0442\u0432\u043e \u0441\u0432\u043e\u0431\u043e\u0434\u043d\u043e\u0433\u043e \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f Linux \u043e\u0442 6.7 \u0434\u043e 6.12.16 , \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 6.6.79 , \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 5.4.68 \u0434\u043e 5.5 , \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 5.8.12 \u0434\u043e 5.15.179 ",
  "\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 __ip_rt_update_pmtu() \u043a\u043e\u043c\u043f\u043e\u043d\u0435\u043d\u0442\u0430 ipv4/route.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\u043f\u0440\u0430\u0432\u0438\u043b\u044c\u043d\u043e\u0435 \u0431\u043b\u043e\u043a\u0438\u0440\u043e\u0432\u0430\u043d\u0438\u0435 \u0440\u0435\u0441\u0443\u0440\u0441\u043e\u0432 (CWE-413)",
  "\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 __ip_rt_update_pmtu() \u043a\u043e\u043c\u043f\u043e\u043d\u0435\u043d\u0442\u0430 ipv4/route.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 \u043d\u0435\u043f\u0440\u0430\u0432\u0438\u043b\u044c\u043d\u043e\u0439 \u0431\u043b\u043e\u043a\u0438\u0440\u043e\u0432\u043a\u043e\u0439 \u0440\u0435\u0441\u0443\u0440\u0441\u043e\u0432. \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/linus/139512191bd06f1b496117c76372b2ce372c9a41\nhttps://git.kernel.org/stable/c/139512191bd06f1b496117c76372b2ce372c9a41\nhttps://git.kernel.org/stable/c/4583748b65dee4d61bd50a2214715b4237bc152a\nhttps://git.kernel.org/stable/c/9b1766d1ff5fe496aabe9fc5f4e34e53f35c11c4\nhttps://git.kernel.org/stable/c/a39f61d212d822b3062d7f70fa0588e50e55664e\nhttps://git.kernel.org/stable/c/ce3c6165fce0f06305c806696882a3ad4b90e33f\nhttps://git.kernel.org/stable/c/ea07480b23225942208f1b754fea1e7ec486d37e\nhttps://github.com/torvalds/linux/commit/139512191bd06f1b496117c76372b2ce372c9a41\nhttps://nvd.nist.gov/vuln/detail/CVE-2025-21766\nhttps://security-tracker.debian.org/tracker/CVE-2025-21766\nhttps://wiki.astralinux.ru/astra-linux-se18-bulletin-2025-0811SE18\nhttps://\u043f\u043e\u0434\u0434\u0435\u0440\u0436\u043a\u0430.\u043d\u043f\u043f\u043a\u0442.\u0440\u0444/bin/view/\u041e\u0421\u043d\u043e\u0432\u0430/\u041e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u044f/2.13/\nhttps://abf.rosa.ru/advisories/ROSA-SA-2026-3261\nhttps://abf.rosa.ru/advisories/ROSA-SA-2026-3262",
  "\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": "\u041f\u041e \u0432\u0438\u0440\u0442\u0443\u0430\u043b\u0438\u0437\u0430\u0446\u0438\u0438/\u041f\u041e \u0432\u0438\u0440\u0442\u0443\u0430\u043b\u044c\u043d\u043e\u0433\u043e \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e-\u0430\u043f\u043f\u0430\u0440\u0430\u0442\u043d\u043e\u0433\u043e \u0441\u0440\u0435\u0434\u0441\u0442\u0432\u0430, \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-413",
  "\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-2025-21766 (GCVE-0-2025-21766)

Vulnerability from cvelistv5 – Published: 2025-02-27 02:18 – Updated: 2026-08-05 11:54

Title

ipv4: use RCU protection in __ip_rt_update_pmtu()

Summary

In the Linux kernel, the following vulnerability has been resolved: ipv4: use RCU protection in __ip_rt_update_pmtu() __ip_rt_update_pmtu() must use RCU protection to make sure the net structure it reads does not disappear.

Severity

8.1 (High)


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

Assigner

Linux mitre root

References

8 references

URL	Tags
https://git.kernel.org/stable/c/ce3c6165fce0f0630…
https://git.kernel.org/stable/c/ea07480b232259422…
https://git.kernel.org/stable/c/9b1766d1ff5fe496a…
https://git.kernel.org/stable/c/4583748b65dee4d61…
https://git.kernel.org/stable/c/a39f61d212d822b30…
https://git.kernel.org/stable/c/139512191bd06f1b4…
https://lists.debian.org/debian-lts-announce/2025…
https://cert-portal.siemens.com/productcert/html/…

Impacted products

5 products

Vendor	Product	Version
Linux	Linux	Affected: 2fbc6e89b2f1403189e624cabaf73e189c5e50c6 , < ce3c6165fce0f06305c806696882a3ad4b90e33f (git) Affected: 2fbc6e89b2f1403189e624cabaf73e189c5e50c6 , < ea07480b23225942208f1b754fea1e7ec486d37e (git) Affected: 2fbc6e89b2f1403189e624cabaf73e189c5e50c6 , < 9b1766d1ff5fe496aabe9fc5f4e34e53f35c11c4 (git) Affected: 2fbc6e89b2f1403189e624cabaf73e189c5e50c6 , < 4583748b65dee4d61bd50a2214715b4237bc152a (git) Affected: 2fbc6e89b2f1403189e624cabaf73e189c5e50c6 , < a39f61d212d822b3062d7f70fa0588e50e55664e (git) Affected: 2fbc6e89b2f1403189e624cabaf73e189c5e50c6 , < 139512191bd06f1b496117c76372b2ce372c9a41 (git) Affected: f415c264176e6095e9dee823e09c5bdd0ee0d337 (git) Affected: 98776a365da509ad923083ae54b38ee521c52742 (git) Affected: 860e2cc78c697c95bc749abb20047239fa1722ea (git) Affected: 2b1be6c925cdf4638811765a9160796291494b89 (git) Affected: 4.14.200 , < 4.15 (semver) Affected: 4.19.148 , < 4.20 (semver) Affected: 5.4.68 , < 5.5 (semver) Affected: 5.8.12 , < 5.9 (semver)
Linux	Linux	Affected: 5.9 Unaffected: 0 , < 5.9 (semver) Unaffected: 5.15.179 , ≤ 5.15.* (semver) Unaffected: 6.1.129 , ≤ 6.1.* (semver) Unaffected: 6.6.79 , ≤ 6.6.* (semver) Unaffected: 6.12.16 , ≤ 6.12.* (semver) Unaffected: 6.13.4 , ≤ 6.13.* (semver) Unaffected: 6.14 , ≤ * (original_commit_for_fix)
Siemens	SIMATIC S7-1500 CPU 1518-4 PN/DP MFP	Affected: V3.1.5 , < * (custom)
Siemens	SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP	Affected: V3.1.5 , < * (custom)
Siemens	SIPLUS S7-1500 CPU 1518-4 PN/DP MFP	Affected: V3.1.5 , < * (custom)

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{
  "containers": {
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          "vendor": "Linux",
          "versions": [
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              "lessThanOrEqual": "6.12.*",
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              "version": "6.12.16",
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              "version": "6.13.4",
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              "status": "unaffected",
              "version": "6.14",
              "versionType": "original_commit_for_fix"
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              "value": "AV:N - `__ip_rt_update_pmtu()` sits directly on the ICMP Fragmentation-Needed processing path \u2014 `icmp_rcv()` \u2192 `icmp_unreach()` \u2192 protocol err handlers (`udp_err`, `raw_err`, `ping_err`, `tcp_v4_err`, `ipip_err`, GRE/vti/esp/ah err) \u2192 `ipv4_sk_update_pmtu()`/`ipv4_update_pmtu()`. A remote host anywhere on the internet reaches it with a single crafted IPv4 ICMP packet, and the attacker-supplied `un.frag.mtu` becomes the value written into the FNHE entry.\nAC:H - The attacker fully controls the read side (unlimited ICMP frag-needed floods), but the freed `struct net` only becomes reachable when a namespace teardown races a long-lived cached `dst` whose `dst-\u003edev` still maps to the dying netns \u2014 network-namespace destruction and the exact preemption window between loading `dev-\u003end_net` and dereferencing it are system state a remote attacker cannot induce.\nPR:N - No authentication or credentials are involved anywhere on the path; the tunnel error handlers (`ipip_err`, GRE, vti, esp4, ah4) and `icmp_err()` dispatch on the quoted inner header alone with no socket or peer verification, so any unauthenticated host can drive `ipv4_update_pmtu()`.\nUI:N - The ICMP error is consumed entirely inside softirq packet-receive processing; no local user opens, mounts, configures, or clicks anything for the vulnerable dereference to run.\nS:U - The use-after-free read and the resulting bogus FIB lookup and FNHE writes are all confined to the kernel\u0027s own security authority; no hypervisor, IOMMU, or sandbox boundary is crossed.\nC:H - The freed `struct net` is not merely read for two sysctls \u2014 it is fed to `fib_lookup()`, which loads `net-\u003eipv4.fib_main`/`fib_default`/`rules_ops` out of reclaimed memory and walks them as FIB tables and rule lists, so a groomed reallocation of the `net_cachep` object turns this into an attacker-directed read of arbitrary kernel addresses.\nI:H - `update_or_create_fnhe()` writes through the `fib_nh_common` returned by that poisoned lookup \u2014 `rcu_assign_pointer(nhc-\u003enhc_exceptions, hash)`, `fnhe-\u003efnhe_pmtu = pmtu`, `fnhe-\u003efnhe_expires` \u2014 with `pmtu` taken verbatim from the attacker\u0027s `ntohs(icmph-\u003eun.frag.mtu)`, yielding a controlled write through a pointer chain rooted in freed memory.\nA:H - Even without weaponization, walking a FIB trie and a fib_rules list off a freed `struct net` reliably faults or corrupts state, producing a KASAN splat, oops, or panic, and the attacker can retrigger it indefinitely by replaying ICMP frag-needed packets."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T11:54:19.559Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/ce3c6165fce0f06305c806696882a3ad4b90e33f"
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          "url": "https://git.kernel.org/stable/c/ea07480b23225942208f1b754fea1e7ec486d37e"
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        },
        {
          "url": "https://git.kernel.org/stable/c/139512191bd06f1b496117c76372b2ce372c9a41"
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      ],
      "title": "ipv4: use RCU protection in __ip_rt_update_pmtu()",
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  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2025-21766",
    "datePublished": "2025-02-27T02:18:16.570Z",
    "dateReserved": "2024-12-29T08:45:45.762Z",
    "dateUpdated": "2026-08-05T11:54:19.559Z",
    "state": "PUBLISHED"
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  "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.