Vulnerability-Lookup

BDU:2025-04432 (CVE-2021-47656)

Vulnerability from fstec – Published: 2025-04-14 – Updated: 2025-04-14 – View on bdu.fstec.ru Fixed

Title

Уязвимость функции jffs2_do_fill_super() модуля fs/jffs2/fs.c поддержки файловой системы jffs2 ядра операционной системы Linux, позволяющая нарушителю оказать воздействие на конфиденциальность, целостность и доступность защищаемой информации

Summary

Уязвимость функции jffs2_do_fill_super() модуля fs/jffs2/fs.c поддержки файловой системы jffs2 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 3.0


                      
                        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-2021-47656

References

21 references

URL
https://www.cve.org/CVERecord?id=CVE-2021-47656
https://git.kernel.org/stable/c/9150cb625b46f68d524f4cfd491f1aafc23e10a9
https://git.kernel.org/stable/c/3bd2454162ec6bbb5503233c804fce6e4b6dcec5
https://git.kernel.org/stable/c/c3b07c875fa8f906f932976460fd14798596f101
https://git.kernel.org/stable/c/30bf7244acf32f19cb722c39f7bc1c2a9f300422
https://git.kernel.org/stable/c/7bb7428dd73991bf4b3a7a61b493ca50046c2b13
https://git.kernel.org/stable/c/7a75740206af5f17e9f3efa384211cba70213da1
https://git.kernel.org/stable/c/22327bd7988f21de3a53c1373f3b81542bfe1f44
https://git.kernel.org/stable/c/8c0f024f29e055840a5a89fe23b96ae3f921afed
https://lore.kernel.org/linux-cve-announce/2025022650-CVE-2021-47656-0abd@gregkh/
https://git.kernel.org/linus/4c7c44ee1650677fbe89d86edbad9497b7679b5c
https://kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.9.311
https://kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.14.276
https://kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.19.238
https://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.4.189
https://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.10.110
https://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.15.33
https://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.16.19
https://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.17.2
https://security-tracker.debian.org/tracker/CVE-2021-47656
https://ubuntu.com/security/CVE-2021-47656

Impacted products

3 products from 2 vendors

Vendors

Canonical Ltd., Сообщество свободного программного обеспечения

Products

Ubuntu, Debian GNU/Linux, Linux

Versions

14.04 LTS (Ubuntu), 16.04 LTS (Ubuntu), 18.04 LTS (Ubuntu), 20.04 LTS (Ubuntu), 11 (Debian GNU/Linux), 12 (Debian GNU/Linux), 22.04 LTS (Ubuntu), от 5.16 до 5.16.18 включительно (Linux), от 5.17 до 5.17.1 включительно (Linux), от 4.10 до 4.14.275 включительно (Linux), от 5.5 до 5.10.109 включительно (Linux), от 5.11 до 5.15.32 включительно (Linux), от 4.15 до 4.19.237 включительно (Linux), от 4.20 до 5.4.188 включительно (Linux), от 2.6.18 до 4.9.310 включительно (Linux)

Product types

Operating system

Platforms

Canonical Ltd. Ubuntu 14.04 LTS, 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 11, Сообщество свободного программного обеспечения Debian GNU/Linux 12, Canonical Ltd. Ubuntu 22.04 LTS, Сообщество свободного программного обеспечения Linux от 5.16 до 5.16.18 включительно, Сообщество свободного программного обеспечения Linux от 5.17 до 5.17.1 включительно, Сообщество свободного программного обеспечения Linux от 4.10 до 4.14.275 включительно, Сообщество свободного программного обеспечения Linux от 5.5 до 5.10.109 включительно, Сообщество свободного программного обеспечения Linux от 5.11 до 5.15.32 включительно, Сообщество свободного программного обеспечения Linux от 4.15 до 4.19.237 включительно, Сообщество свободного программного обеспечения Linux от 4.20 до 5.4.188 включительно, Сообщество свободного программного обеспечения Linux от 2.6.18 до 4.9.310 включительно

Mitigations

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": "14.04 LTS (Ubuntu), 16.04 LTS (Ubuntu), 18.04 LTS (Ubuntu), 20.04 LTS (Ubuntu), 11 (Debian GNU/Linux), 12 (Debian GNU/Linux), 22.04 LTS (Ubuntu), \u043e\u0442 5.16 \u0434\u043e 5.16.18 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e (Linux), \u043e\u0442 5.17 \u0434\u043e 5.17.1 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e (Linux), \u043e\u0442 4.10 \u0434\u043e 4.14.275 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e (Linux), \u043e\u0442 5.5 \u0434\u043e 5.10.109 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e (Linux), \u043e\u0442 5.11 \u0434\u043e 5.15.32 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e (Linux), \u043e\u0442 4.15 \u0434\u043e 4.19.237 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e (Linux), \u043e\u0442 4.20 \u0434\u043e 5.4.188 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e (Linux), \u043e\u0442 2.6.18 \u0434\u043e 4.9.310 \u0432\u043a\u043b\u044e\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e (Linux)",
  "\u0412\u043e\u0437\u043c\u043e\u0436\u043d\u044b\u0435 \u043c\u0435\u0440\u044b \u043f\u043e \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0438\u044e": "\u0412 \u0443\u0441\u043b\u043e\u0432\u0438\u044f\u0445 \u043e\u0442\u0441\u0443\u0442\u0441\u0442\u0432\u0438\u044f \u043e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u0439 \u0431\u0435\u0437\u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438 \u043e\u0442 \u043f\u0440\u043e\u0438\u0437\u0432\u043e\u0434\u0438\u0442\u0435\u043b\u044f \u0440\u0435\u043a\u043e\u043c\u0435\u043d\u0434\u0443\u0435\u0442\u0441\u044f \u043f\u0440\u0438\u0434\u0435\u0440\u0436\u0438\u0432\u0430\u0442\u044c\u0441\u044f \"\u0420\u0435\u043a\u043e\u043c\u0435\u043d\u0434\u0430\u0446\u0438\u0439 \u043f\u043e \u0431\u0435\u0437\u043e\u043f\u0430\u0441\u043d\u043e\u0439 \u043d\u0430\u0441\u0442\u0440\u043e\u0439\u043a\u0435 \u043e\u043f\u0435\u0440\u0430\u0446\u0438\u043e\u043d\u043d\u044b\u0445 \u0441\u0438\u0441\u0442\u0435\u043c LINUX\", \u0438\u0437\u043b\u043e\u0436\u0435\u043d\u043d\u044b\u0445 \u0432 \u043c\u0435\u0442\u043e\u0434\u0438\u0447\u0435\u0441\u043a\u043e\u043c \u0434\u043e\u043a\u0443\u043c\u0435\u043d\u0442\u0435 \u0424\u0421\u0422\u042d\u041a \u0420\u043e\u0441\u0441\u0438\u0438, \u0443\u0442\u0432\u0435\u0440\u0436\u0434\u0451\u043d\u043d\u043e\u043c 25 \u0434\u0435\u043a\u0430\u0431\u0440\u044f 2022 \u0433\u043e\u0434\u0430.\n\n\u0418\u0441\u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u043d\u0438\u0435 \u0440\u0435\u043a\u043e\u043c\u0435\u043d\u0434\u0430\u0446\u0438\u0439:\n\u0414\u043b\u044f Linux:\nhttps://git.kernel.org/stable/c/9150cb625b46f68d524f4cfd491f1aafc23e10a9\nhttps://git.kernel.org/stable/c/3bd2454162ec6bbb5503233c804fce6e4b6dcec5\nhttps://git.kernel.org/stable/c/c3b07c875fa8f906f932976460fd14798596f101\nhttps://git.kernel.org/stable/c/30bf7244acf32f19cb722c39f7bc1c2a9f300422\nhttps://git.kernel.org/stable/c/7bb7428dd73991bf4b3a7a61b493ca50046c2b13\nhttps://git.kernel.org/stable/c/7a75740206af5f17e9f3efa384211cba70213da1\nhttps://git.kernel.org/stable/c/22327bd7988f21de3a53c1373f3b81542bfe1f44\nhttps://git.kernel.org/stable/c/8c0f024f29e055840a5a89fe23b96ae3f921afed\nhttps://lore.kernel.org/linux-cve-announce/2025022650-CVE-2021-47656-0abd@gregkh/\nhttps://git.kernel.org/linus/4c7c44ee1650677fbe89d86edbad9497b7679b5c\nhttps://kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.9.311\nhttps://kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.14.276\nhttps://kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.19.238\nhttps://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.4.189\nhttps://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.10.110\nhttps://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.15.33\nhttps://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.16.19\nhttps://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.17.2\n\n\u0414\u043b\u044f Debian GNU/Linux:\nhttps://security-tracker.debian.org/tracker/CVE-2021-47656\n\n\u0414\u043b\u044f Ubuntu:\nhttps://ubuntu.com/security/CVE-2021-47656",
  "\u0414\u0430\u0442\u0430 \u0432\u044b\u044f\u0432\u043b\u0435\u043d\u0438\u044f": "16.03.2022",
  "\u0414\u0430\u0442\u0430 \u043f\u043e\u0441\u043b\u0435\u0434\u043d\u0435\u0433\u043e \u043e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u044f": "14.04.2025",
  "\u0414\u0430\u0442\u0430 \u043f\u0443\u0431\u043b\u0438\u043a\u0430\u0446\u0438\u0438": "14.04.2025",
  "\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440": "BDU:2025-04432",
  "\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-2021-47656",
  "\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 14.04 LTS , 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 11 , \u0421\u043e\u043e\u0431\u0449\u0435\u0441\u0442\u0432\u043e \u0441\u0432\u043e\u0431\u043e\u0434\u043d\u043e\u0433\u043e \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f Debian GNU/Linux 12 , Canonical Ltd. Ubuntu 22.04 LTS , \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 5.16.18 \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 5.17 \u0434\u043e 5.17.1 \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 4.14.275 \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 5.5 \u0434\u043e 5.10.109 \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 5.15.32 \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 4.19.237 \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 5.4.188 \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 2.6.18 \u0434\u043e 4.9.310 \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 jffs2_do_fill_super() \u043c\u043e\u0434\u0443\u043b\u044f fs/jffs2/fs.c \u043f\u043e\u0434\u0434\u0435\u0440\u0436\u043a\u0438 \u0444\u0430\u0439\u043b\u043e\u0432\u043e\u0439 \u0441\u0438\u0441\u0442\u0435\u043c\u044b jffs2 \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 jffs2_do_fill_super() \u043c\u043e\u0434\u0443\u043b\u044f fs/jffs2/fs.c \u043f\u043e\u0434\u0434\u0435\u0440\u0436\u043a\u0438 \u0444\u0430\u0439\u043b\u043e\u0432\u043e\u0439 \u0441\u0438\u0441\u0442\u0435\u043c\u044b jffs2 \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://www.cve.org/CVERecord?id=CVE-2021-47656\nhttps://git.kernel.org/stable/c/9150cb625b46f68d524f4cfd491f1aafc23e10a9\nhttps://git.kernel.org/stable/c/3bd2454162ec6bbb5503233c804fce6e4b6dcec5\nhttps://git.kernel.org/stable/c/c3b07c875fa8f906f932976460fd14798596f101\nhttps://git.kernel.org/stable/c/30bf7244acf32f19cb722c39f7bc1c2a9f300422\nhttps://git.kernel.org/stable/c/7bb7428dd73991bf4b3a7a61b493ca50046c2b13\nhttps://git.kernel.org/stable/c/7a75740206af5f17e9f3efa384211cba70213da1\nhttps://git.kernel.org/stable/c/22327bd7988f21de3a53c1373f3b81542bfe1f44\nhttps://git.kernel.org/stable/c/8c0f024f29e055840a5a89fe23b96ae3f921afed\nhttps://lore.kernel.org/linux-cve-announce/2025022650-CVE-2021-47656-0abd@gregkh/\nhttps://git.kernel.org/linus/4c7c44ee1650677fbe89d86edbad9497b7679b5c\nhttps://kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.9.311\nhttps://kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.14.276\nhttps://kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.19.238\nhttps://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.4.189\nhttps://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.10.110\nhttps://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.15.33\nhttps://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.16.19\nhttps://kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.17.2\nhttps://security-tracker.debian.org/tracker/CVE-2021-47656\nhttps://ubuntu.com/security/CVE-2021-47656",
  "\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-2021-47656 (GCVE-0-2021-47656)

Vulnerability from cvelistv5 – Published: 2025-02-26 01:54 – Updated: 2026-08-05 08:48

Title

jffs2: fix use-after-free in jffs2_clear_xattr_subsystem

Summary

In the Linux kernel, the following vulnerability has been resolved: jffs2: fix use-after-free in jffs2_clear_xattr_subsystem When we mount a jffs2 image, assume that the first few blocks of the image are normal and contain at least one xattr-related inode, but the next block is abnormal. As a result, an error is returned in jffs2_scan_eraseblock(). jffs2_clear_xattr_subsystem() is then called in jffs2_build_filesystem() and then again in jffs2_do_fill_super(). Finally we can observe the following report: ================================================================== BUG: KASAN: use-after-free in jffs2_clear_xattr_subsystem+0x95/0x6ac Read of size 8 at addr ffff8881243384e0 by task mount/719 Call Trace: dump_stack+0x115/0x16b jffs2_clear_xattr_subsystem+0x95/0x6ac jffs2_do_fill_super+0x84f/0xc30 jffs2_fill_super+0x2ea/0x4c0 mtd_get_sb+0x254/0x400 mtd_get_sb_by_nr+0x4f/0xd0 get_tree_mtd+0x498/0x840 jffs2_get_tree+0x25/0x30 vfs_get_tree+0x8d/0x2e0 path_mount+0x50f/0x1e50 do_mount+0x107/0x130 __se_sys_mount+0x1c5/0x2f0 __x64_sys_mount+0xc7/0x160 do_syscall_64+0x45/0x70 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Allocated by task 719: kasan_save_stack+0x23/0x60 __kasan_kmalloc.constprop.0+0x10b/0x120 kasan_slab_alloc+0x12/0x20 kmem_cache_alloc+0x1c0/0x870 jffs2_alloc_xattr_ref+0x2f/0xa0 jffs2_scan_medium.cold+0x3713/0x4794 jffs2_do_mount_fs.cold+0xa7/0x2253 jffs2_do_fill_super+0x383/0xc30 jffs2_fill_super+0x2ea/0x4c0 [...] Freed by task 719: kmem_cache_free+0xcc/0x7b0 jffs2_free_xattr_ref+0x78/0x98 jffs2_clear_xattr_subsystem+0xa1/0x6ac jffs2_do_mount_fs.cold+0x5e6/0x2253 jffs2_do_fill_super+0x383/0xc30 jffs2_fill_super+0x2ea/0x4c0 [...] The buggy address belongs to the object at ffff8881243384b8 which belongs to the cache jffs2_xattr_ref of size 48 The buggy address is located 40 bytes inside of 48-byte region [ffff8881243384b8, ffff8881243384e8) [...] ================================================================== The triggering of the BUG is shown in the following stack: ----------------------------------------------------------- jffs2_fill_super jffs2_do_fill_super jffs2_do_mount_fs jffs2_build_filesystem jffs2_scan_medium jffs2_scan_eraseblock <--- ERROR jffs2_clear_xattr_subsystem <--- free jffs2_clear_xattr_subsystem <--- free again ----------------------------------------------------------- An error is returned in jffs2_do_mount_fs(). If the error is returned by jffs2_sum_init(), the jffs2_clear_xattr_subsystem() does not need to be executed. If the error is returned by jffs2_build_filesystem(), the jffs2_clear_xattr_subsystem() also does not need to be executed again. So move jffs2_clear_xattr_subsystem() from 'out_inohash' to 'out_root' to fix this UAF problem.

Severity

7.8 (High)


                        
                          CVSS:3.1/AV:L/AC:L/PR:N/UI:R/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 2025-02-27 17:59 UTC

CWE

CWE-416 - Use After Free

Assigner

Linux mitre root

References

9 references

URL	Tags
https://git.kernel.org/stable/c/9150cb625b46f68d5…
https://git.kernel.org/stable/c/3bd2454162ec6bbb5…
https://git.kernel.org/stable/c/c3b07c875fa8f906f…
https://git.kernel.org/stable/c/30bf7244acf32f19c…
https://git.kernel.org/stable/c/7bb7428dd73991bf4…
https://git.kernel.org/stable/c/7a75740206af5f17e…
https://git.kernel.org/stable/c/22327bd7988f21de3…
https://git.kernel.org/stable/c/8c0f024f29e055840…
https://git.kernel.org/stable/c/4c7c44ee1650677fb…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: aa98d7cf59b5b0764d3502662053489585faf2fe , < 9150cb625b46f68d524f4cfd491f1aafc23e10a9 (git) Affected: aa98d7cf59b5b0764d3502662053489585faf2fe , < 3bd2454162ec6bbb5503233c804fce6e4b6dcec5 (git) Affected: aa98d7cf59b5b0764d3502662053489585faf2fe , < c3b07c875fa8f906f932976460fd14798596f101 (git) Affected: aa98d7cf59b5b0764d3502662053489585faf2fe , < 30bf7244acf32f19cb722c39f7bc1c2a9f300422 (git) Affected: aa98d7cf59b5b0764d3502662053489585faf2fe , < 7bb7428dd73991bf4b3a7a61b493ca50046c2b13 (git) Affected: aa98d7cf59b5b0764d3502662053489585faf2fe , < 7a75740206af5f17e9f3efa384211cba70213da1 (git) Affected: aa98d7cf59b5b0764d3502662053489585faf2fe , < 22327bd7988f21de3a53c1373f3b81542bfe1f44 (git) Affected: aa98d7cf59b5b0764d3502662053489585faf2fe , < 8c0f024f29e055840a5a89fe23b96ae3f921afed (git) Affected: aa98d7cf59b5b0764d3502662053489585faf2fe , < 4c7c44ee1650677fbe89d86edbad9497b7679b5c (git)
Linux	Linux	Affected: 2.6.18 Unaffected: 0 , < 2.6.18 (semver) Unaffected: 4.9.311 , ≤ 4.9.* (semver) Unaffected: 4.14.276 , ≤ 4.14.* (semver) Unaffected: 4.19.238 , ≤ 4.19.* (semver) Unaffected: 5.4.189 , ≤ 5.4.* (semver) Unaffected: 5.10.110 , ≤ 5.10.* (semver) Unaffected: 5.15.33 , ≤ 5.15.* (semver) Unaffected: 5.16.19 , ≤ 5.16.* (semver) Unaffected: 5.17.2 , ≤ 5.17.* (semver) Unaffected: 5.18 , ≤ * (original_commit_for_fix)

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      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\njffs2: fix use-after-free in jffs2_clear_xattr_subsystem\n\nWhen we mount a jffs2 image, assume that the first few blocks of\nthe image are normal and contain at least one xattr-related inode,\nbut the next block is abnormal. As a result, an error is returned\nin jffs2_scan_eraseblock(). jffs2_clear_xattr_subsystem() is then\ncalled in jffs2_build_filesystem() and then again in\njffs2_do_fill_super().\n\nFinally we can observe the following report:\n ==================================================================\n BUG: KASAN: use-after-free in jffs2_clear_xattr_subsystem+0x95/0x6ac\n Read of size 8 at addr ffff8881243384e0 by task mount/719\n\n Call Trace:\n  dump_stack+0x115/0x16b\n  jffs2_clear_xattr_subsystem+0x95/0x6ac\n  jffs2_do_fill_super+0x84f/0xc30\n  jffs2_fill_super+0x2ea/0x4c0\n  mtd_get_sb+0x254/0x400\n  mtd_get_sb_by_nr+0x4f/0xd0\n  get_tree_mtd+0x498/0x840\n  jffs2_get_tree+0x25/0x30\n  vfs_get_tree+0x8d/0x2e0\n  path_mount+0x50f/0x1e50\n  do_mount+0x107/0x130\n  __se_sys_mount+0x1c5/0x2f0\n  __x64_sys_mount+0xc7/0x160\n  do_syscall_64+0x45/0x70\n  entry_SYSCALL_64_after_hwframe+0x44/0xa9\n\n Allocated by task 719:\n  kasan_save_stack+0x23/0x60\n  __kasan_kmalloc.constprop.0+0x10b/0x120\n  kasan_slab_alloc+0x12/0x20\n  kmem_cache_alloc+0x1c0/0x870\n  jffs2_alloc_xattr_ref+0x2f/0xa0\n  jffs2_scan_medium.cold+0x3713/0x4794\n  jffs2_do_mount_fs.cold+0xa7/0x2253\n  jffs2_do_fill_super+0x383/0xc30\n  jffs2_fill_super+0x2ea/0x4c0\n [...]\n\n Freed by task 719:\n  kmem_cache_free+0xcc/0x7b0\n  jffs2_free_xattr_ref+0x78/0x98\n  jffs2_clear_xattr_subsystem+0xa1/0x6ac\n  jffs2_do_mount_fs.cold+0x5e6/0x2253\n  jffs2_do_fill_super+0x383/0xc30\n  jffs2_fill_super+0x2ea/0x4c0\n [...]\n\n The buggy address belongs to the object at ffff8881243384b8\n  which belongs to the cache jffs2_xattr_ref of size 48\n The buggy address is located 40 bytes inside of\n  48-byte region [ffff8881243384b8, ffff8881243384e8)\n [...]\n ==================================================================\n\nThe triggering of the BUG is shown in the following stack:\n-----------------------------------------------------------\njffs2_fill_super\n  jffs2_do_fill_super\n    jffs2_do_mount_fs\n      jffs2_build_filesystem\n        jffs2_scan_medium\n          jffs2_scan_eraseblock        \u003c--- ERROR\n        jffs2_clear_xattr_subsystem    \u003c--- free\n    jffs2_clear_xattr_subsystem        \u003c--- free again\n-----------------------------------------------------------\n\nAn error is returned in jffs2_do_mount_fs(). If the error is returned\nby jffs2_sum_init(), the jffs2_clear_xattr_subsystem() does not need to\nbe executed. If the error is returned by jffs2_build_filesystem(), the\njffs2_clear_xattr_subsystem() also does not need to be executed again.\nSo move jffs2_clear_xattr_subsystem() from \u0027out_inohash\u0027 to \u0027out_root\u0027\nto fix this UAF problem."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - The bug is reached only through the local mount path (mount \u2192 jffs2_get_tree \u2192 get_tree_mtd \u2192 jffs2_fill_super \u2192 jffs2_do_fill_super \u2192 jffs2_do_mount_fs \u2192 jffs2_build_filesystem), parsing an MTD/JFFS2 image; there is no network-facing consumer.\nAC:L - An attacker who crafts the image fully controls the trigger\u2014place valid XREF/XATTR nodes in early eraseblocks so jffs2_alloc_xattr_ref() populates xref_temp, then make a later block fail jffs2_scan_eraseblock()\u2014with no race or attacker-uncontrollable condition.\nPR:N - The attacker needs no account on the target; they only supply the crafted JFFS2/MTD image (firmware blob, flash/SD contents), and CAP_SYS_ADMIN belongs to the victim or tooling that mounts it, matching the crafted-filesystem-image pattern.\nUI:R - Exploitation requires a victim (root, firmware updater, or automounter) to mount the attacker-supplied JFFS2 image so the failing scan hits the double clear_xattr path.\nS:U - The use-after-free corrupts kernel slab memory within the same host OS security authority; no VM escape, IOMMU bypass, or other cross-boundary compromise occurs.\nC:H - jffs2_clear_xattr_subsystem() frees xref_temp without NULLing it, so the second call reads ref-\u003enext from freed jffs2_xattr_ref slab objects; per guidance a UAF enables arbitrary kernel memory disclosure.\nI:H - The second pass double-frees attacker-populated jffs2_xattr_ref objects, enabling classic heap spraying and overlapping allocations for arbitrary write / control-flow hijack.\nA:H - The KASAN-confirmed use-after-free during mount produces a kernel oops/panic even without full exploitation, and is repeatable on every mount of the crafted image."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T08:48:47.063Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/9150cb625b46f68d524f4cfd491f1aafc23e10a9"
        },
        {
          "url": "https://git.kernel.org/stable/c/3bd2454162ec6bbb5503233c804fce6e4b6dcec5"
        },
        {
          "url": "https://git.kernel.org/stable/c/c3b07c875fa8f906f932976460fd14798596f101"
        },
        {
          "url": "https://git.kernel.org/stable/c/30bf7244acf32f19cb722c39f7bc1c2a9f300422"
        },
        {
          "url": "https://git.kernel.org/stable/c/7bb7428dd73991bf4b3a7a61b493ca50046c2b13"
        },
        {
          "url": "https://git.kernel.org/stable/c/7a75740206af5f17e9f3efa384211cba70213da1"
        },
        {
          "url": "https://git.kernel.org/stable/c/22327bd7988f21de3a53c1373f3b81542bfe1f44"
        },
        {
          "url": "https://git.kernel.org/stable/c/8c0f024f29e055840a5a89fe23b96ae3f921afed"
        },
        {
          "url": "https://git.kernel.org/stable/c/4c7c44ee1650677fbe89d86edbad9497b7679b5c"
        }
      ],
      "title": "jffs2: fix use-after-free in jffs2_clear_xattr_subsystem",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2021-47656",
    "datePublished": "2025-02-26T01:54:20.069Z",
    "dateReserved": "2025-02-26T01:48:21.521Z",
    "dateUpdated": "2026-08-05T08:48:47.063Z",
    "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.