CVE-2026-64414 (GCVE-0-2026-64414)
Vulnerability from cvelistv5 – Published: 2026-07-25 08:50 – Updated: 2026-08-17 04:55
VLAI
EPSS
VEX
Title
netfilter: handle unreadable frags
Summary
In the Linux kernel, the following vulnerability has been resolved:
netfilter: handle unreadable frags
sashiko reports:
When an skb with unreadable fragments (such as from devmem TCP, where
skb_frags_readable(skb) returns false) is processed by the u32 module,
skb_copy_bits() will safely return a negative error code [..]
xt_u32: bail out with hotdrop in this case.
gather_frags: return -1, just as if we had no fragment header.
nfnetlink_queue: restrict to the linear part.
nfnetlink_log: restrict to the linear part.
v2:
- skb_zerocopy helpers don't copy readable flag, i.e. nfnetlink_queue
is broken too
xt_u32 shouldn't return true if hotdrop was set.
Severity
7.5 (High)
Assigner
References
Impacted products
2 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Linux | Linux |
Affected:
65249feb6b3df9e17bab5911ee56fa7b0971e231 , < 3b13e7635795394705920cca1e1db7e4ca2e334b
(git)
Affected: 65249feb6b3df9e17bab5911ee56fa7b0971e231 , < fc5bfe63bacf8a3ae307b62b34206406ca733354 (git) Affected: 65249feb6b3df9e17bab5911ee56fa7b0971e231 , < 57056be3ec12e7d9ecd20a60d4060f510e4f284c (git) Affected: 65249feb6b3df9e17bab5911ee56fa7b0971e231 , < da5b58478a9c1b85608c9e40a3b8432d071b409e (git) |
guessed | |
| Linux | Linux |
Affected:
6.12
Unaffected: 0 , < 6.12 (semver) Unaffected: 6.12.96 , ≤ 6.12.* (semver) Unaffected: 6.18.39 , ≤ 6.18.* (semver) Unaffected: 7.1.4 , ≤ 7.1.* (semver) Unaffected: 7.2 , ≤ * (original_commit_for_fix) |
guessed |
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}
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"current_release_date": "2026-09-17T12:42:25+00:00",
"cve": "CVE-2026-64414",
"id": "CVE-2026-64414",
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"source": "Red Hat CSAF VEX",
"status": "final",
"title": "kernel: netfilter: handle unreadable frags",
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-64414.json",
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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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