Vulnerability-Lookup

BDU:2024-03687 (CVE-2021-46936)

Vulnerability from fstec – Published: 2024-05-15 – Updated: 2024-09-16 – View on bdu.fstec.ru Fixed

Title

Уязвимость функции inet_init() в модуле net/ipv4/af_inet.c реализации протокола IPv4 ядра операционной системы Linux, позволяющая нарушителю оказать воздействие на конфиденциальность, целостность и доступность защищаемой информации

Summary

Уязвимость функции inet_init() в модуле net/ipv4/af_inet.c реализации протокола IPv4 ядра операционной системы Linux связана с использованием памяти после её освобождения. 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 3.0


                      
                        CVSS:3.0/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-2021-46936

References

22 references

URL
https://git.kernel.org/stable/c/e22e45fc9e41bf9fcc1e92cfb78eb92786728ef0
https://git.kernel.org/stable/c/08eacbd141e2495d2fcdde84358a06c4f95cbb13
https://git.kernel.org/stable/c/15579e1301f856ad9385d720c9267c11032a5022
https://git.kernel.org/stable/c/e73164e89d1be561228a4534e1091369ee4ba41a
https://git.kernel.org/stable/c/fe5838c22b986c1190f1dce9aa09bf6a491c1a69
https://git.kernel.org/stable/c/a8e1944b44f94f5c5f530e434c5eaee787254566
https://git.kernel.org/stable/c/2386e81a1d277f540e1285565c9d41d531bb69d4
https://git.kernel.org/stable/c/5c2fe20ad37ff56070ae0acb34152333976929b4
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-46936
https://lore.kernel.org/linux-cve-announce/2024022751-CVE-2021-46936-2f8a@gregkh/T/#u
https://git.kernel.org/linus/e22e45fc9e41bf9fcc1e92cfb78eb92786728ef0
https://www.cve.org/CVERecord?id=CVE-2021-46936
https://ubuntu.com/security/notices/USN-6739-1
https://kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.4.298
https://kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.9.296
https://kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.14.261
https://kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.19.224
https://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.4.170
https://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.10.90
https://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.15.13
http://repo.red-soft.ru/redos/7.3c/x86_64/updates/
https://cve.omp.ru/bb25402

Impacted products

3 products from 3 vendors

Vendors

ООО «Ред Софт», Сообщество свободного программного обеспечения, ООО "Открытая мобильная платформа"

Products

РЕД ОС (запись в едином реестре российских программ №3751), Linux, ОС Аврора (запись в едином реестре российских программ №1543)

Versions

7.3 (РЕД ОС), от 5.5 до 5.10.89 включительно (Linux), от 5.11 до 5.15.12 включительно (Linux), от 4.15 до 4.19.223 включительно (Linux), от 4.20 до 5.4.169 включительно (Linux), от 4.0 до 4.4.297 включительно (Linux), от 4.5 до 4.9.295 включительно (Linux), от 4.10 до 4.14.260 включительно (Linux), до 5.1.1 включительно (ОС Аврора)

Product types

Operating system

Platforms

ООО «Ред Софт» РЕД ОС 7.3 (запись в едином реестре российских программ №3751), Сообщество свободного программного обеспечения Linux от 5.5 до 5.10.89 включительно, Сообщество свободного программного обеспечения Linux от 5.11 до 5.15.12 включительно, Сообщество свободного программного обеспечения Linux от 4.15 до 4.19.223 включительно, Сообщество свободного программного обеспечения Linux от 4.20 до 5.4.169 включительно, Сообщество свободного программного обеспечения Linux от 4.0 до 4.4.297 включительно, Сообщество свободного программного обеспечения Linux от 4.5 до 4.9.295 включительно, Сообщество свободного программного обеспечения Linux от 4.10 до 4.14.260 включительно, ООО "Открытая мобильная платформа" ОС Аврора до 5.1.1 включительно Mashtab TrustPhone T1 (запись в едином реестре российских программ №1543), ООО "Открытая мобильная платформа" ОС Аврора до 5.1.1 включительно Fplus T1100 (запись в едином реестре российских программ №1543), ООО "Открытая мобильная платформа" ОС Аврора до 5.1.1 включительно Fplus T800 (запись в едином реестре российских программ №1543)

Mitigations

Использование рекомендаций: Для Linux: https://git.kernel.org/stable/c/e22e45fc9e41bf9fcc1e92cfb78eb92786728ef0 https://git.kernel.org/stable/c/08eacbd141e2495d2fcdde84358a06c4f95cbb13 https://git.kernel.org/stable/c/15579e1301f856ad9385d720c9267c11032a5022 https://git.kernel.org/stable/c/e73164e89d1be561228a4534e1091369ee4ba41a https://git.kernel.org/stable/c/fe5838c22b986c1190f1dce9aa09bf6a491c1a69 https://git.kernel.org/stable/c/a8e1944b44f94f5c5f530e434c5eaee787254566 https://git.kernel.org/stable/c/2386e81a1d277f540e1285565c9d41d531bb69d4 https://git.kernel.org/stable/c/5c2fe20ad37ff56070ae0acb34152333976929b4 https://kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.4.298 https://kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.9.296 https://kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.14.261 https://kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.19.224 https://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.4.170 https://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.10.90 https://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.15.13 Для РедОС: http://repo.red-soft.ru/redos/7.3c/x86_64/updates/ Для ОС Аврора: https://cve.omp.ru/bb25402

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": "\u041e\u041e\u041e \u00ab\u0420\u0435\u0434 \u0421\u043e\u0444\u0442\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 \"\u041e\u0442\u043a\u0440\u044b\u0442\u0430\u044f \u043c\u043e\u0431\u0438\u043b\u044c\u043d\u0430\u044f \u043f\u043b\u0430\u0442\u0444\u043e\u0440\u043c\u0430\"",
  "\u0412\u0435\u0440\u0441\u0438\u044f \u041f\u041e": "7.3 (\u0420\u0415\u0414 \u041e\u0421), \u043e\u0442 5.5 \u0434\u043e 5.10.89 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e (Linux), \u043e\u0442 5.11 \u0434\u043e 5.15.12 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e (Linux), \u043e\u0442 4.15 \u0434\u043e 4.19.223 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e (Linux), \u043e\u0442 4.20 \u0434\u043e 5.4.169 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e (Linux), \u043e\u0442 4.0 \u0434\u043e 4.4.297 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e (Linux), \u043e\u0442 4.5 \u0434\u043e 4.9.295 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e (Linux), \u043e\u0442 4.10 \u0434\u043e 4.14.260 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e (Linux), \u0434\u043e 5.1.1 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e (\u041e\u0421 \u0410\u0432\u0440\u043e\u0440\u0430)",
  "\u0412\u043e\u0437\u043c\u043e\u0436\u043d\u044b\u0435 \u043c\u0435\u0440\u044b \u043f\u043e \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0438\u044e": "\u0418\u0441\u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u043d\u0438\u0435 \u0440\u0435\u043a\u043e\u043c\u0435\u043d\u0434\u0430\u0446\u0438\u0439:\n\u0414\u043b\u044f Linux:\nhttps://git.kernel.org/stable/c/e22e45fc9e41bf9fcc1e92cfb78eb92786728ef0\nhttps://git.kernel.org/stable/c/08eacbd141e2495d2fcdde84358a06c4f95cbb13\nhttps://git.kernel.org/stable/c/15579e1301f856ad9385d720c9267c11032a5022\nhttps://git.kernel.org/stable/c/e73164e89d1be561228a4534e1091369ee4ba41a\nhttps://git.kernel.org/stable/c/fe5838c22b986c1190f1dce9aa09bf6a491c1a69\nhttps://git.kernel.org/stable/c/a8e1944b44f94f5c5f530e434c5eaee787254566\nhttps://git.kernel.org/stable/c/2386e81a1d277f540e1285565c9d41d531bb69d4\nhttps://git.kernel.org/stable/c/5c2fe20ad37ff56070ae0acb34152333976929b4\nhttps://kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.4.298\nhttps://kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.9.296\nhttps://kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.14.261\nhttps://kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.19.224\nhttps://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.4.170\nhttps://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.10.90\nhttps://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.15.13\n\n\u0414\u043b\u044f \u0420\u0435\u0434\u041e\u0421: http://repo.red-soft.ru/redos/7.3c/x86_64/updates/\n\n\u0414\u043b\u044f \u041e\u0421 \u0410\u0432\u0440\u043e\u0440\u0430:\nhttps://cve.omp.ru/bb25402",
  "\u0414\u0430\u0442\u0430 \u0432\u044b\u044f\u0432\u043b\u0435\u043d\u0438\u044f": "29.12.2021",
  "\u0414\u0430\u0442\u0430 \u043f\u043e\u0441\u043b\u0435\u0434\u043d\u0435\u0433\u043e \u043e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u044f": "16.09.2024",
  "\u0414\u0430\u0442\u0430 \u043f\u0443\u0431\u043b\u0438\u043a\u0430\u0446\u0438\u0438": "15.05.2024",
  "\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440": "BDU:2024-03687",
  "\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-2021-46936",
  "\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": "\u0420\u0415\u0414 \u041e\u0421 (\u0437\u0430\u043f\u0438\u0441\u044c \u0432 \u0435\u0434\u0438\u043d\u043e\u043c \u0440\u0435\u0435\u0441\u0442\u0440\u0435 \u0440\u043e\u0441\u0441\u0438\u0439\u0441\u043a\u0438\u0445 \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c \u21163751), Linux, \u041e\u0421 \u0410\u0432\u0440\u043e\u0440\u0430 (\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 \u21161543)",
  "\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": "\u041e\u041e\u041e \u00ab\u0420\u0435\u0434 \u0421\u043e\u0444\u0442\u00bb \u0420\u0415\u0414 \u041e\u0421 7.3  (\u0437\u0430\u043f\u0438\u0441\u044c \u0432 \u0435\u0434\u0438\u043d\u043e\u043c \u0440\u0435\u0435\u0441\u0442\u0440\u0435 \u0440\u043e\u0441\u0441\u0438\u0439\u0441\u043a\u0438\u0445 \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c \u21163751), \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 5.5 \u0434\u043e 5.10.89 \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 5.11 \u0434\u043e 5.15.12 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e , \u0421\u043e\u043e\u0431\u0449\u0435\u0441\u0442\u0432\u043e \u0441\u0432\u043e\u0431\u043e\u0434\u043d\u043e\u0433\u043e \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f Linux \u043e\u0442 4.15 \u0434\u043e 4.19.223 \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 4.20 \u0434\u043e 5.4.169 \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 4.0 \u0434\u043e 4.4.297 \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 4.5 \u0434\u043e 4.9.295 \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 4.10 \u0434\u043e 4.14.260 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e , \u041e\u041e\u041e \"\u041e\u0442\u043a\u0440\u044b\u0442\u0430\u044f \u043c\u043e\u0431\u0438\u043b\u044c\u043d\u0430\u044f \u043f\u043b\u0430\u0442\u0444\u043e\u0440\u043c\u0430\" \u041e\u0421 \u0410\u0432\u0440\u043e\u0440\u0430 \u0434\u043e 5.1.1 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e Mashtab TrustPhone T1 (\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 \u21161543), \u041e\u041e\u041e \"\u041e\u0442\u043a\u0440\u044b\u0442\u0430\u044f \u043c\u043e\u0431\u0438\u043b\u044c\u043d\u0430\u044f \u043f\u043b\u0430\u0442\u0444\u043e\u0440\u043c\u0430\" \u041e\u0421 \u0410\u0432\u0440\u043e\u0440\u0430 \u0434\u043e 5.1.1 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e Fplus T1100 (\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 \u21161543), \u041e\u041e\u041e \"\u041e\u0442\u043a\u0440\u044b\u0442\u0430\u044f \u043c\u043e\u0431\u0438\u043b\u044c\u043d\u0430\u044f \u043f\u043b\u0430\u0442\u0444\u043e\u0440\u043c\u0430\" \u041e\u0421 \u0410\u0432\u0440\u043e\u0440\u0430 \u0434\u043e 5.1.1 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e Fplus T800 (\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 \u21161543)",
  "\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 inet_init() \u0432 \u043c\u043e\u0434\u0443\u043b\u0435 net/ipv4/af_inet.c \u0440\u0435\u0430\u043b\u0438\u0437\u0430\u0446\u0438\u0438 \u043f\u0440\u043e\u0442\u043e\u043a\u043e\u043b\u0430 IPv4 \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 inet_init() \u0432 \u043c\u043e\u0434\u0443\u043b\u0435 net/ipv4/af_inet.c \u0440\u0435\u0430\u043b\u0438\u0437\u0430\u0446\u0438\u0438 \u043f\u0440\u043e\u0442\u043e\u043a\u043e\u043b\u0430 IPv4 \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 \u0438\u0441\u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u043d\u0438\u0435\u043c \u043f\u0430\u043c\u044f\u0442\u0438 \u043f\u043e\u0441\u043b\u0435 \u0435\u0451 \u043e\u0441\u0432\u043e\u0431\u043e\u0436\u0434\u0435\u043d\u0438\u044f. \u042d\u043a\u0441\u043f\u043b\u0443\u0430\u0442\u0430\u0446\u0438\u044f \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438 \u043c\u043e\u0436\u0435\u0442 \u043f\u043e\u0437\u0432\u043e\u043b\u0438\u0442\u044c \u043d\u0430\u0440\u0443\u0448\u0438\u0442\u0435\u043b\u044e \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/e22e45fc9e41bf9fcc1e92cfb78eb92786728ef0\nhttps://git.kernel.org/stable/c/08eacbd141e2495d2fcdde84358a06c4f95cbb13\nhttps://git.kernel.org/stable/c/15579e1301f856ad9385d720c9267c11032a5022\nhttps://git.kernel.org/stable/c/e73164e89d1be561228a4534e1091369ee4ba41a\nhttps://git.kernel.org/stable/c/fe5838c22b986c1190f1dce9aa09bf6a491c1a69\nhttps://git.kernel.org/stable/c/a8e1944b44f94f5c5f530e434c5eaee787254566\nhttps://git.kernel.org/stable/c/2386e81a1d277f540e1285565c9d41d531bb69d4\nhttps://git.kernel.org/stable/c/5c2fe20ad37ff56070ae0acb34152333976929b4\nhttps://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-46936\nhttps://lore.kernel.org/linux-cve-announce/2024022751-CVE-2021-46936-2f8a@gregkh/T/#u\nhttps://git.kernel.org/linus/e22e45fc9e41bf9fcc1e92cfb78eb92786728ef0\nhttps://www.cve.org/CVERecord?id=CVE-2021-46936\nhttps://ubuntu.com/security/notices/USN-6739-1\nhttps://kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.4.298\nhttps://kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.9.296\nhttps://kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.14.261\nhttps://kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.19.224\nhttps://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.4.170\nhttps://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.10.90\nhttps://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.15.13\nhttp://repo.red-soft.ru/redos/7.3c/x86_64/updates/\nhttps://cve.omp.ru/bb25402",
  "\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 3.0 \u0441\u043e\u0441\u0442\u0430\u0432\u043b\u044f\u0435\u0442 7,8)"
}

CVE-2021-46936 (GCVE-0-2021-46936)

Vulnerability from cvelistv5 – Published: 2024-02-27 09:44 – Updated: 2026-08-05 08:45

Title

net: fix use-after-free in tw_timer_handler

Summary

In the Linux kernel, the following vulnerability has been resolved: net: fix use-after-free in tw_timer_handler A real world panic issue was found as follow in Linux 5.4. BUG: unable to handle page fault for address: ffffde49a863de28 PGD 7e6fe62067 P4D 7e6fe62067 PUD 7e6fe63067 PMD f51e064067 PTE 0 RIP: 0010:tw_timer_handler+0x20/0x40 Call Trace: <IRQ> call_timer_fn+0x2b/0x120 run_timer_softirq+0x1ef/0x450 __do_softirq+0x10d/0x2b8 irq_exit+0xc7/0xd0 smp_apic_timer_interrupt+0x68/0x120 apic_timer_interrupt+0xf/0x20 This issue was also reported since 2017 in the thread [1], unfortunately, the issue was still can be reproduced after fixing DCCP. The ipv4_mib_exit_net is called before tcp_sk_exit_batch when a net namespace is destroyed since tcp_sk_ops is registered befrore ipv4_mib_ops, which means tcp_sk_ops is in the front of ipv4_mib_ops in the list of pernet_list. There will be a use-after-free on net->mib.net_statistics in tw_timer_handler after ipv4_mib_exit_net if there are some inflight time-wait timers. This bug is not introduced by commit f2bf415cfed7 ("mib: add net to NET_ADD_STATS_BH") since the net_statistics is a global variable instead of dynamic allocation and freeing. Actually, commit 61a7e26028b9 ("mib: put net statistics on struct net") introduces the bug since it put net statistics on struct net and free it when net namespace is destroyed. Moving init_ipv4_mibs() to the front of tcp_init() to fix this bug and replace pr_crit() with panic() since continuing is meaningless when init_ipv4_mibs() fails. [1] https://groups.google.com/g/syzkaller/c/p1tn-_Kc6l4/m/smuL_FMAAgAJ?pli=1

Severity

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: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2024-09-10 16:01 UTC

Assigner

Linux mitre root

References

8 references

URL	Tags
https://git.kernel.org/stable/c/15579e1301f856ad9…
https://git.kernel.org/stable/c/e73164e89d1be5612…
https://git.kernel.org/stable/c/5c2fe20ad37ff5607…
https://git.kernel.org/stable/c/a8e1944b44f94f5c5…
https://git.kernel.org/stable/c/fe5838c22b986c119…
https://git.kernel.org/stable/c/2386e81a1d277f540…
https://git.kernel.org/stable/c/08eacbd141e2495d2…
https://git.kernel.org/stable/c/e22e45fc9e41bf9fc…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 61a7e26028b94805fd686a6dc9dbd9941f8f19b0 , < 15579e1301f856ad9385d720c9267c11032a5022 (git) Affected: 61a7e26028b94805fd686a6dc9dbd9941f8f19b0 , < e73164e89d1be561228a4534e1091369ee4ba41a (git) Affected: 61a7e26028b94805fd686a6dc9dbd9941f8f19b0 , < 5c2fe20ad37ff56070ae0acb34152333976929b4 (git) Affected: 61a7e26028b94805fd686a6dc9dbd9941f8f19b0 , < a8e1944b44f94f5c5f530e434c5eaee787254566 (git) Affected: 61a7e26028b94805fd686a6dc9dbd9941f8f19b0 , < fe5838c22b986c1190f1dce9aa09bf6a491c1a69 (git) Affected: 61a7e26028b94805fd686a6dc9dbd9941f8f19b0 , < 2386e81a1d277f540e1285565c9d41d531bb69d4 (git) Affected: 61a7e26028b94805fd686a6dc9dbd9941f8f19b0 , < 08eacbd141e2495d2fcdde84358a06c4f95cbb13 (git) Affected: 61a7e26028b94805fd686a6dc9dbd9941f8f19b0 , < e22e45fc9e41bf9fcc1e92cfb78eb92786728ef0 (git)
Linux	Linux	Affected: 2.6.27 Unaffected: 0 , < 2.6.27 (semver) Unaffected: 4.4.298 , ≤ 4.4.* (semver) Unaffected: 4.9.296 , ≤ 4.9.* (semver) Unaffected: 4.14.261 , ≤ 4.14.* (semver) Unaffected: 4.19.224 , ≤ 4.19.* (semver) Unaffected: 5.4.170 , ≤ 5.4.* (semver) Unaffected: 5.10.90 , ≤ 5.10.* (semver) Unaffected: 5.15.13 , ≤ 5.15.* (semver) Unaffected: 5.16 , ≤ * (original_commit_for_fix)

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          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: fix use-after-free in tw_timer_handler\n\nA real world panic issue was found as follow in Linux 5.4.\n\n    BUG: unable to handle page fault for address: ffffde49a863de28\n    PGD 7e6fe62067 P4D 7e6fe62067 PUD 7e6fe63067 PMD f51e064067 PTE 0\n    RIP: 0010:tw_timer_handler+0x20/0x40\n    Call Trace:\n     \u003cIRQ\u003e\n     call_timer_fn+0x2b/0x120\n     run_timer_softirq+0x1ef/0x450\n     __do_softirq+0x10d/0x2b8\n     irq_exit+0xc7/0xd0\n     smp_apic_timer_interrupt+0x68/0x120\n     apic_timer_interrupt+0xf/0x20\n\nThis issue was also reported since 2017 in the thread [1],\nunfortunately, the issue was still can be reproduced after fixing\nDCCP.\n\nThe ipv4_mib_exit_net is called before tcp_sk_exit_batch when a net\nnamespace is destroyed since tcp_sk_ops is registered befrore\nipv4_mib_ops, which means tcp_sk_ops is in the front of ipv4_mib_ops\nin the list of pernet_list. There will be a use-after-free on\nnet-\u003emib.net_statistics in tw_timer_handler after ipv4_mib_exit_net\nif there are some inflight time-wait timers.\n\nThis bug is not introduced by commit f2bf415cfed7 (\"mib: add net to\nNET_ADD_STATS_BH\") since the net_statistics is a global variable\ninstead of dynamic allocation and freeing. Actually, commit\n61a7e26028b9 (\"mib: put net statistics on struct net\") introduces\nthe bug since it put net statistics on struct net and free it when\nnet namespace is destroyed.\n\nMoving init_ipv4_mibs() to the front of tcp_init() to fix this bug\nand replace pr_crit() with panic() since continuing is meaningless\nwhen init_ipv4_mibs() fails.\n\n[1] https://groups.google.com/g/syzkaller/c/p1tn-_Kc6l4/m/smuL_FMAAgAJ?pli=1"
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              "value": "AV:L - The bug is triggered by destroying a network namespace while TCP TIME_WAIT timers remain armed, which requires local syscalls (clone/unshare, socket connect/close); a remote packet alone cannot tear down the netns or hit this teardown ordering.\nAC:L - An attacker fully controls both sides\u2014creating TIME_WAIT sockets (including short-timeout tw_kill paths) and destroying the netns\u2014so the race between ipv4_mib_exit_net freeing stats and tcp_sk_exit_batch purging timers is attacker-driven and has been reproduced in the wild and by syzkaller.\nPR:L - An unprivileged process can create a user+net namespace (CLONE_NEWUSER|CLONE_NEWNET), open loopback TCP connections that enter TIME_WAIT, and exit the netns; CAP_SYS_ADMIN inside the user namespace is sufficient and does not require host root.\nUI:N - Exploitation requires no victim action; the attacker creates the sockets and destroys the namespace themselves.\nS:U - Impact is confined to the host kernel\u2019s networking subsystem authority; this is a standard kernel UAF/privilege-escalation class bug, not a VM/IOMMU/sandbox boundary escape.\nC:H - This is a use-after-free on net-\u003emib.net_statistics in tw_timer_handler; UAF of freed kernel heap/percpu memory can be leveraged for information disclosure once the object is reused.\nI:H - tw_timer_handler performs __NET_INC_STATS writes into the already-freed percpu MIB, yielding a memory-corruption write primitive that can be escalated via heap reuse to integrity compromise or code execution.\nA:H - The vulnerability causes a real-world kernel page-fault panic in softirq context (tw_timer_handler), so availability impact is a full kernel oops/panic."
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    "assignerShortName": "Linux",
    "cveId": "CVE-2021-46936",
    "datePublished": "2024-02-27T09:44:02.758Z",
    "dateReserved": "2024-02-25T13:45:52.720Z",
    "dateUpdated": "2026-08-05T08:45:10.624Z",
    "state": "PUBLISHED"
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}

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.