CVE-2026-53250 (GCVE-0-2026-53250)
Vulnerability from cvelistv5 – Published: 2026-06-25 08:39 – Updated: 2026-09-14 11:58
VLAI
EPSS
VEX
Title
xsk: cache csum_start/csum_offset to fix TOCTOU in xsk_skb_metadata()
Summary
In the Linux kernel, the following vulnerability has been resolved:
xsk: cache csum_start/csum_offset to fix TOCTOU in xsk_skb_metadata()
The TX metadata area resides in the UMEM buffer which is memory-mapped
and concurrently writable by userspace. In xsk_skb_metadata(),
csum_start and csum_offset are read from shared memory for bounds
validation, then read again for skb assignment. A malicious userspace
application can race to overwrite these values between the two reads,
bypassing the bounds check and causing out-of-bounds memory access
during checksum computation in the transmit path.
Fix this by reading csum_start and csum_offset into local variables
once, then using the local copies for both validation and assignment.
Note that other metadata fields (flags, launch_time) and the cached
csum fields may be mutually inconsistent due to concurrent userspace
writes, but this is benign: the only security-critical invariant is
that each field's validated value is the same one used, which local
caching guarantees.
Severity
7.8 (High)
Assigner
References
Impacted products
2 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Linux | Linux |
Affected:
48eb03dd26304c24f03bdbb9382e89c8564e71df , < eb778aed8a9b2381668fcb1247ae4fa011224768
(git)
Affected: 48eb03dd26304c24f03bdbb9382e89c8564e71df , < 0dfe05b938435892875e07771170051346412df9 (git) Affected: 48eb03dd26304c24f03bdbb9382e89c8564e71df , < bfdfd2706d5fb2cd496a1506e680daf979309c8b (git) Affected: 48eb03dd26304c24f03bdbb9382e89c8564e71df , < 22ba97ea9cc1f63a0d0244fae38057ed452b6ac7 (git) |
guessed | |
| Linux | Linux |
Affected:
6.8
Unaffected: 0 , < 6.8 (semver) Unaffected: 6.12.110 , ≤ 6.12.* (semver) Unaffected: 6.18.36 , ≤ 6.18.* (semver) Unaffected: 7.0.13 , ≤ 7.0.* (semver) Unaffected: 7.1 , ≤ * (original_commit_for_fix) |
guessed |
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"current_release_date": "2026-08-13T16:50:23+00:00",
"cve": "CVE-2026-53250",
"id": "CVE-2026-53250",
"initial_release_date": "2026-06-25T00:00:00+00:00",
"product_status:known_affected": "184",
"product_status:known_not_affected": "90",
"source": "Red Hat CSAF VEX",
"status": "final",
"title": "kernel: Linux kernel (xsk): Out-of-bounds memory access via TOCTOU race condition",
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-53250.json",
"version": "3"
},
"suse_vex": {
"aggregate_severity": "important",
"current_release_date": "2026-09-10T16:56:18Z",
"cve": "CVE-2026-53250",
"id": "CVE-2026-53250",
"initial_release_date": "2026-06-26T02:08:39Z",
"product_status:first_fixed": "2",
"product_status:known_affected": "423",
"product_status:known_not_affected": "279",
"product_status:recommended": "281",
"source": "SUSE CSAF VEX",
"status": "interim",
"title": "SUSE CVE CVE-2026-53250",
"url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-53250.json",
"version": "16"
}
}
}
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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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