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CVE-2021-47232
can: j1939: fix Use-after-Free, hold skb ref while in use
Critical9.8EPSS 0.62%
- Published
- Updated
- Reserved
- Assigned by
- Linux
Description
In the Linux kernel, the following vulnerability has been resolved: can: j1939: fix Use-after-Free, hold skb ref while in use This patch fixes a Use-after-Free found by the syzbot. The problem is that a skb is taken from the per-session skb queue, without incrementing the ref count. This leads to a Use-after-Free if the skb is taken concurrently from the session queue due to a CTS.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| LinuxCNA (assigner) | 3.1 | Critical9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| CISA-ADPADP (enrichment) | 3.1 | High8.4 | CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Modified | 3.1 | Critical9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.62% · top 50% of all CVEs (6 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: total
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The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 9.8.
Weakness
Affected products
- affected 9d71dd0c70099914fcd063135da3c580865e924c – < 22cba878abf646cd3a02ee7c8c2cef7afe66a256
- affected 9d71dd0c70099914fcd063135da3c580865e924c – < 509ab6bfdd0c76daebbad0f0af07da712116de22
- affected 9d71dd0c70099914fcd063135da3c580865e924c – < 1071065eeb33d32b7d98c2ce7591881ae7381705
- affected 9d71dd0c70099914fcd063135da3c580865e924c – < 2030043e616cab40f510299f09b636285e0a3678
- affected 5.4
- unaffected < 5.4
- unaffected 5.4.128 – ≤ 5.4.*
- unaffected 5.10.46 – ≤ 5.10.*
- unaffected 5.12.13 – ≤ 5.12.*
- unaffected 5.13 – ≤ *
References (4)
- https://git.kernel.org/stable/c/22cba878abf646cd3a02ee7c8c2cef7afe66a256 (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/509ab6bfdd0c76daebbad0f0af07da712116de22 (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/1071065eeb33d32b7d98c2ce7591881ae7381705 (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/2030043e616cab40f510299f09b636285e0a3678 (opens in a new tab)x_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2021-47232)Record last updated .