CVE-2025-21669 (GCVE-0-2025-21669)
Vulnerability from cvelistv5 – Published: 2025-01-31 11:25 – Updated: 2026-08-05 11:53
VLAI
EPSS
VEX
Title
vsock/virtio: discard packets if the transport changes
Summary
In the Linux kernel, the following vulnerability has been resolved:
vsock/virtio: discard packets if the transport changes
If the socket has been de-assigned or assigned to another transport,
we must discard any packets received because they are not expected
and would cause issues when we access vsk->transport.
A possible scenario is described by Hyunwoo Kim in the attached link,
where after a first connect() interrupted by a signal, and a second
connect() failed, we can find `vsk->transport` at NULL, leading to a
NULL pointer dereference.
Severity
7.8 (High)
5.5 (Medium)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-10-01 19:52 UTC
CWE
- CWE-476 - NULL Pointer Dereference
Assigner
References
9 references
Impacted products
3 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Linux | Linux |
Affected:
c0cfa2d8a788fcf45df5bf4070ab2474c88d543a , < 18a7fc371d1dbf8deff16c2dd9292bcc73f43040
(git)
Affected: c0cfa2d8a788fcf45df5bf4070ab2474c88d543a , < 6486915fa661584d70e8e7e4068c6c075c67dd6d (git) Affected: c0cfa2d8a788fcf45df5bf4070ab2474c88d543a , < 88244163bc7e7b0ce9dd7bf4c8a563b41525c3ee (git) Affected: c0cfa2d8a788fcf45df5bf4070ab2474c88d543a , < d88b249e14bd0ee1e46bbe4f456e22e01b8c68de (git) Affected: c0cfa2d8a788fcf45df5bf4070ab2474c88d543a , < 677579b641af109613564460a4e3bdcb16850b61 (git) Affected: c0cfa2d8a788fcf45df5bf4070ab2474c88d543a , < 2cb7c756f605ec02ffe562fb26828e4bcc5fdfc1 (git) |
guessed | |
| Linux | Linux |
Affected:
5.5
Unaffected: 0 , < 5.5 (semver) Unaffected: 5.10.234 , ≤ 5.10.* (semver) Unaffected: 5.15.177 , ≤ 5.15.* (semver) Unaffected: 6.1.127 , ≤ 6.1.* (semver) Unaffected: 6.6.74 , ≤ 6.6.* (semver) Unaffected: 6.12.11 , ≤ 6.12.* (semver) Unaffected: 6.13 , ≤ * (original_commit_for_fix) |
guessed | |
| Siemens | SIMATIC S7-1500 TM MFP - GNU/Linux subsystem |
Affected:
0 , < *
(custom)
|
guessed |
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{
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"product_status:fixed": "612",
"product_status:known_affected": "98",
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"status": "final",
"title": "kernel: vsock/virtio: discard packets if the transport changes",
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-21669.json",
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}
],
"title": "CVE Program Container"
},
{
"affected": [
{
"defaultStatus": "unknown",
"product": "SIMATIC S7-1500 TM MFP - GNU/Linux subsystem",
"vendor": "Siemens",
"versions": [
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"references": [
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}
],
"x_adpType": "supplier"
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{
"metrics": [
{
"cvssV3_1": {
"attackComplexity": "LOW",
"attackVector": "LOCAL",
"availabilityImpact": "HIGH",
"baseScore": 5.5,
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"scope": "UNCHANGED",
"userInteraction": "NONE",
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},
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"options": [
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}
],
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}
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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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