CVE-2021-47232 (GCVE-0-2021-47232)
Vulnerability from cvelistv5 – Published: 2024-05-21 14:19 – Updated: 2026-08-05 08:46
VLAI
EPSS
VEX
Title
can: j1939: fix Use-after-Free, hold skb ref while in use
Summary
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.
Severity
9.8 (Critical)
8.4 (High)
SSVC
Exploitation: none
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2024-05-28 19:03 UTC
CWE
- CWE-416 - Use After Free
Assigner
References
Impacted products
12 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Linux | Linux |
Affected:
9d71dd0c70099914fcd063135da3c580865e924c , < 22cba878abf646cd3a02ee7c8c2cef7afe66a256
(git)
Affected: 9d71dd0c70099914fcd063135da3c580865e924c , < 509ab6bfdd0c76daebbad0f0af07da712116de22 (git) Affected: 9d71dd0c70099914fcd063135da3c580865e924c , < 1071065eeb33d32b7d98c2ce7591881ae7381705 (git) Affected: 9d71dd0c70099914fcd063135da3c580865e924c , < 2030043e616cab40f510299f09b636285e0a3678 (git) |
guessed | |
| Linux | Linux |
Affected:
5.4
Unaffected: 0 , < 5.4 (semver) Unaffected: 5.4.128 , ≤ 5.4.* (semver) Unaffected: 5.10.46 , ≤ 5.10.* (semver) Unaffected: 5.12.13 , ≤ 5.12.* (semver) Unaffected: 5.13 , ≤ * (original_commit_for_fix) |
guessed | |
| linux | linux_kernel |
Affected:
9d71dd0c7009 , < 22cba878abf6
(custom)
cpe:2.3:o:linux:linux_kernel:-:*:*:*:*:*:*:* |
||
| linux | linux_kernel |
Affected:
9d71dd0c7009 , < 509ab6bfdd0c
(custom)
cpe:2.3:o:linux:linux_kernel:-:*:*:*:*:*:*:* |
||
| linux | linux_kernel |
Affected:
9d71dd0c7009 , < 1071065eeb33
(custom)
cpe:2.3:o:linux:linux_kernel:-:*:*:*:*:*:*:* |
||
| linux | linux_kernel |
Affected:
9d71dd0c7009 , < 2030043e616c
(custom)
cpe:2.3:o:linux:linux_kernel:-:*:*:*:*:*:*:* |
||
| linux | linux_kernel |
Unaffected:
5.4.128 , < 5.5
(custom)
cpe:2.3:o:linux:linux_kernel:-:*:*:*:*:*:*:* |
||
| linux | linux_kernel |
Unaffected:
5.10.46 , < 5.11
(custom)
cpe:2.3:o:linux:linux_kernel:-:*:*:*:*:*:*:* |
||
| linux | linux_kernel |
Unaffected:
5.12.13 , < 5.13
(custom)
cpe:2.3:o:linux:linux_kernel:-:*:*:*:*:*:*:* |
||
| linux | linux_kernel |
Unaffected:
5.13
cpe:2.3:o:linux:linux_kernel:-:*:*:*:*:*:*:* |
||
| linux | linux_kernel |
Unaffected:
0 , < 5.4
(custom)
cpe:2.3:o:linux:linux_kernel:-:*:*:*:*:*:*:* |
||
| linux | linux_kernel |
Affected:
5.4
cpe:2.3:o:linux:linux_kernel:5.4:-:*:*:*:*:*:* |
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
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.
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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.
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.
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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.
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