CVE-2026-52981 (GCVE-0-2026-52981)
Vulnerability from cvelistv5 – Published: 2026-06-24 16:28 – Updated: 2026-08-05 12:32
VLAI
EPSS
VEX
Title
neigh: let neigh_xmit take skb ownership
Summary
In the Linux kernel, the following vulnerability has been resolved:
neigh: let neigh_xmit take skb ownership
neigh_xmit always releases the skb, except when no neighbour table is
found. But even the first added user of neigh_xmit (mpls) relied on
neigh_xmit to release the skb (or queue it for tx).
sashiko reported:
If neigh_xmit() is called with an uninitialized neighbor table (for
example, NEIGH_ND_TABLE when IPv6 is disabled), it returns -EAFNOSUPPORT
and bypasses its internal out_kfree_skb error path. Because the return
value of neigh_xmit() is ignored here, does this leak the SKB?
Assume full ownership and remove the last code path that doesn't
xmit or free skb.
Severity
7.5 (High)
Assigner
References
6 references
Impacted products
2 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Linux | Linux |
Affected:
4fd3d7d9e868ffbdb0e7a67c5c8e9dfdcd846a62 , < 8a89054a1ec0767aec25ed2bbac933da6ba3cf5a
(git)
Affected: 4fd3d7d9e868ffbdb0e7a67c5c8e9dfdcd846a62 , < 9247d59ca15bf60a57dca08103f055d8a4340877 (git) Affected: 4fd3d7d9e868ffbdb0e7a67c5c8e9dfdcd846a62 , < 0084712e0bee204b284510cdb63182fd5a30c2b7 (git) Affected: 4fd3d7d9e868ffbdb0e7a67c5c8e9dfdcd846a62 , < 63063ba60d2dc334e34f1e3f9271d7f3f6f30307 (git) Affected: 4fd3d7d9e868ffbdb0e7a67c5c8e9dfdcd846a62 , < 445e45a2c3a078316a62d2d331a570cf34ef5079 (git) Affected: 4fd3d7d9e868ffbdb0e7a67c5c8e9dfdcd846a62 , < 4438113be604ee67a7bf4f81da6e1cca41332ce4 (git) |
guessed | |
| Linux | Linux |
Affected:
4.1
Unaffected: 0 , < 4.1 (semver) Unaffected: 6.1.175 , ≤ 6.1.* (semver) Unaffected: 6.6.141 , ≤ 6.6.* (semver) Unaffected: 6.12.91 , ≤ 6.12.* (semver) Unaffected: 6.18.33 , ≤ 6.18.* (semver) Unaffected: 7.0.10 , ≤ 7.0.* (semver) Unaffected: 7.1 , ≤ * (original_commit_for_fix) |
guessed |
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}
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}
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{
"url": "https://git.kernel.org/stable/c/4438113be604ee67a7bf4f81da6e1cca41332ce4"
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}
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"lastModified": "2026-07-14T16:51:14.830",
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"id": "CVE-2026-52981",
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"source": "Red Hat CSAF VEX",
"status": "final",
"title": "kernel: neigh: let neigh_xmit take skb ownership",
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-52981.json",
"version": "3"
},
"suse_vex": {
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"current_release_date": "2026-10-01T01:02:28Z",
"cve": "CVE-2026-52981",
"id": "CVE-2026-52981",
"initial_release_date": "2026-06-27T01:55:03Z",
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"product_status:recommended": "273",
"source": "SUSE CSAF VEX",
"status": "interim",
"title": "SUSE CVE CVE-2026-52981",
"url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-52981.json",
"version": "11"
}
}
}
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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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