CVE-2025-21764 (GCVE-0-2025-21764)
Vulnerability from cvelistv5 – Published: 2025-02-27 02:18 – Updated: 2026-09-08 08:40
VLAI
EPSS
VEX
Title
ndisc: use RCU protection in ndisc_alloc_skb()
Summary
In the Linux kernel, the following vulnerability has been resolved:
ndisc: use RCU protection in ndisc_alloc_skb()
ndisc_alloc_skb() can be called without RTNL or RCU being held.
Add RCU protection to avoid possible UAF.
Severity
7.8 (High)
SSVC
Exploitation: none
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-02-27 17:57 UTC
CWE
- CWE-416 - Use After Free
Assigner
References
12 references
Impacted products
6 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Linux | Linux |
Affected:
de09334b9326632bbf1a74bfd8b01866cbbf2f61 , < 96fc896d0e5b37c12808df797397fb16f3080879
(git)
Affected: de09334b9326632bbf1a74bfd8b01866cbbf2f61 , < c30893ef3d9cde8e7e8e4fd06b53d2c935bbccb1 (git) Affected: de09334b9326632bbf1a74bfd8b01866cbbf2f61 , < b870256dd2a5648d5ed2f22316b3ac29a7e5ed63 (git) Affected: de09334b9326632bbf1a74bfd8b01866cbbf2f61 , < 3c2d705f5adf5d860aaef90cb4211c0fde2ba66d (git) Affected: de09334b9326632bbf1a74bfd8b01866cbbf2f61 , < 9e0ec817eb41a55327a46cd3ce331a9868d60304 (git) Affected: de09334b9326632bbf1a74bfd8b01866cbbf2f61 , < bbec88e4108e8d6fb468d3817fa652140a44ff28 (git) Affected: de09334b9326632bbf1a74bfd8b01866cbbf2f61 , < cd1065f92eb7ff21b9ba5308a86f33d1670bf926 (git) Affected: de09334b9326632bbf1a74bfd8b01866cbbf2f61 , < 628e6d18930bbd21f2d4562228afe27694f66da9 (git) |
guessed | |
| Linux | Linux |
Affected:
3.9
Unaffected: 0 , < 3.9 (semver) Unaffected: 5.4.291 , ≤ 5.4.* (semver) Unaffected: 5.10.235 , ≤ 5.10.* (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) |
guessed | |
| Siemens | SIMATIC S7-1500 CPU 1518-4 PN/DP MFP |
Affected:
V3.1.6 , < *
(custom)
|
guessed | |
| Siemens | SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP |
Affected:
V3.1.6 , < *
(custom)
|
guessed | |
| Siemens | SIMATIC S7-1500 TM MFP - GNU/Linux subsystem |
Affected:
0 , < *
(custom)
|
guessed | |
| Siemens | SIPLUS S7-1500 CPU 1518-4 PN/DP MFP |
Affected:
V3.1.6 , < *
(custom)
|
guessed |
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},
{
"url": "https://git.kernel.org/stable/c/3c2d705f5adf5d860aaef90cb4211c0fde2ba66d"
},
{
"url": "https://git.kernel.org/stable/c/9e0ec817eb41a55327a46cd3ce331a9868d60304"
},
{
"url": "https://git.kernel.org/stable/c/bbec88e4108e8d6fb468d3817fa652140a44ff28"
},
{
"url": "https://git.kernel.org/stable/c/cd1065f92eb7ff21b9ba5308a86f33d1670bf926"
},
{
"url": "https://git.kernel.org/stable/c/628e6d18930bbd21f2d4562228afe27694f66da9"
}
],
"title": "ndisc: use RCU protection in ndisc_alloc_skb()",
"x_generator": {
"engine": "bippy-1.2.0"
}
}
},
"cveMetadata": {
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"assignerShortName": "Linux",
"cveId": "CVE-2025-21764",
"datePublished": "2025-02-27T02:18:15.598Z",
"dateReserved": "2024-12-29T08:45:45.761Z",
"dateUpdated": "2026-09-08T08:40:32.725Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
}
}
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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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