CVE-2026-43304 (GCVE-0-2026-43304)
Vulnerability from cvelistv5 – Published: 2026-05-08 13:11 – Updated: 2026-08-05 12:27
VLAI
EPSS
VEX
Title
libceph: define and enforce CEPH_MAX_KEY_LEN
Summary
In the Linux kernel, the following vulnerability has been resolved:
libceph: define and enforce CEPH_MAX_KEY_LEN
When decoding the key, verify that the key material would fit into
a fixed-size buffer in process_auth_done() and generally has a sane
length.
The new CEPH_MAX_KEY_LEN check replaces the existing check for a key
with no key material which is a) not universal since CEPH_CRYPTO_NONE
has to be excluded and b) doesn't provide much value since a smaller
than needed key is just as invalid as no key -- this has to be handled
elsewhere anyway.
Severity
9.8 (Critical)
Assigner
References
7 references
Impacted products
2 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Linux | Linux |
Affected:
cd1a677cad994021b19665ed476aea63f5d54f31 , < 6405e8c680974bb74e2c98d5249fb52c7b12a6c6
(git)
Affected: cd1a677cad994021b19665ed476aea63f5d54f31 , < 8d745d38c88ecbed95f6b2b39857bf89f35a3244 (git) Affected: cd1a677cad994021b19665ed476aea63f5d54f31 , < e1dc45d97975f9db65694d234fbddf1915176e16 (git) Affected: cd1a677cad994021b19665ed476aea63f5d54f31 , < 1b275bd49e58752efb83767a5d1aed41356c5e64 (git) Affected: cd1a677cad994021b19665ed476aea63f5d54f31 , < c1a0f5f1e5e7e98c36a362ec3d1fcfd9932931ed (git) Affected: cd1a677cad994021b19665ed476aea63f5d54f31 , < d82467c07b03a27c3c5469b62bb3b726305a80bb (git) Affected: cd1a677cad994021b19665ed476aea63f5d54f31 , < ac431d597a9bdfc2ba6b314813f29a6ef2b4a3bf (git) |
guessed | |
| Linux | Linux |
Affected:
5.11
Unaffected: 0 , < 5.11 (semver) Unaffected: 5.15.202 , ≤ 5.15.* (semver) Unaffected: 6.1.165 , ≤ 6.1.* (semver) Unaffected: 6.6.128 , ≤ 6.6.* (semver) Unaffected: 6.12.75 , ≤ 6.12.* (semver) Unaffected: 6.18.16 , ≤ 6.18.* (semver) Unaffected: 6.19.6 , ≤ 6.19.* (semver) Unaffected: 7.0 , ≤ * (original_commit_for_fix) |
guessed |
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"current_release_date": "2026-07-14T11:37:43+00:00",
"cve": "CVE-2026-43304",
"id": "CVE-2026-43304",
"initial_release_date": "2026-05-08T00:00:00+00:00",
"product_status:known_affected": "260",
"product_status:known_not_affected": "14",
"source": "Red Hat CSAF VEX",
"status": "final",
"title": "kernel: libceph: define and enforce CEPH_MAX_KEY_LEN",
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-43304.json",
"version": "3"
},
"suse_vex": {
"aggregate_severity": "moderate",
"current_release_date": "2026-10-01T01:20:25Z",
"cve": "CVE-2026-43304",
"id": "CVE-2026-43304",
"initial_release_date": "2026-05-13T03:35:38Z",
"product_status:known_affected": "530",
"product_status:known_not_affected": "175",
"product_status:recommended": "250",
"source": "SUSE CSAF VEX",
"status": "interim",
"title": "SUSE CVE CVE-2026-43304",
"url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-43304.json",
"version": "17"
}
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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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