CVE-2026-63823 (GCVE-0-2026-63823)
Vulnerability from cvelistv5 – Published: 2026-07-19 12:02 – Updated: 2026-08-17 04:51
VLAI
EPSS
VEX
Title
keys: Pin request_key_auth payload in instantiate paths
Summary
In the Linux kernel, the following vulnerability has been resolved:
keys: Pin request_key_auth payload in instantiate paths
A: request_key() B: KEYCTL_INSTANTIATE_IOV
================ =========================
create auth key
store rka in auth key
wait for helper
get auth key
load rka from auth key
copy user payload
sleep on #PF
helper completed
detach and free rka
destroy auth key
wake up
use rka->target_key
**USE-AFTER-FREE**
Give request_key_auth payloads a refcount. Take a payload reference while
authkey->sem stabilizes the payload and revocation state. Hold that
reference across the instantiate and reject paths. Drop the auth key
owning reference from revoke and destroy.
[jarkko: Replaced the first two paragraphs of text with an actual
concurrency scenario.]
Severity
7.8 (High)
Assigner
References
8 references
Impacted products
2 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Linux | Linux |
Affected:
b5f545c880a2a47947ba2118b2509644ab7a2969 , < d8274181b0f28d450b42489723a5ba81042158d7
(git)
Affected: b5f545c880a2a47947ba2118b2509644ab7a2969 , < 4982bfabce6b33b3c9eddb4fb900fe5568b7cf91 (git) Affected: b5f545c880a2a47947ba2118b2509644ab7a2969 , < 708709c65a1832a99b0eef8ae46e343ddaca3d06 (git) Affected: b5f545c880a2a47947ba2118b2509644ab7a2969 , < 35ab4db86774d82389e4b9559e26ab7f68d8e395 (git) Affected: b5f545c880a2a47947ba2118b2509644ab7a2969 , < f9b68632ac93cc742f2e411021c4dbfe452ea0c2 (git) Affected: b5f545c880a2a47947ba2118b2509644ab7a2969 , < 7216ce8cb12fee44e309503955bb83806b106129 (git) Affected: b5f545c880a2a47947ba2118b2509644ab7a2969 , < 83c0a1cb296d955d5f4d1f0bd8a769ba8ed8c29f (git) Affected: b5f545c880a2a47947ba2118b2509644ab7a2969 , < fd15b457a86939c38aa12116adabd8ff686c5e51 (git) |
guessed | |
| Linux | Linux |
Affected:
2.6.16
Unaffected: 0 , < 2.6.16 (semver) Unaffected: 5.10.260 , ≤ 5.10.* (semver) Unaffected: 5.15.211 , ≤ 5.15.* (semver) Unaffected: 6.1.177 , ≤ 6.1.* (semver) Unaffected: 6.6.144 , ≤ 6.6.* (semver) Unaffected: 6.12.95 , ≤ 6.12.* (semver) Unaffected: 6.18.38 , ≤ 6.18.* (semver) Unaffected: 7.1.3 , ≤ 7.1.* (semver) Unaffected: 7.2 , ≤ * (original_commit_for_fix) |
guessed |
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"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nkeys: Pin request_key_auth payload in instantiate paths\n\nA: request_key() B: KEYCTL_INSTANTIATE_IOV\n================ =========================\n\ncreate auth key\nstore rka in auth key\nwait for helper\n get auth key\n load rka from auth key\n copy user payload\n sleep on #PF\n\nhelper completed\ndetach and free rka\ndestroy auth key\n wake up\n use rka-\u003etarget_key\n **USE-AFTER-FREE**\n\nGive request_key_auth payloads a refcount. Take a payload reference while\nauthkey-\u003esem stabilizes the payload and revocation state. Hold that\nreference across the instantiate and reject paths. Drop the auth key\nowning reference from revoke and destroy.\n\n[jarkko: Replaced the first two paragraphs of text with an actual\n concurrency scenario.]"
}
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}
]
}
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"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nkeys: Pin request_key_auth payload in instantiate paths\n\nA: request_key() B: KEYCTL_INSTANTIATE_IOV\n================ =========================\n\ncreate auth key\nstore rka in auth key\nwait for helper\n get auth key\n load rka from auth key\n copy user payload\n sleep on #PF\n\nhelper completed\ndetach and free rka\ndestroy auth key\n wake up\n use rka-\u003etarget_key\n **USE-AFTER-FREE**\n\nGive request_key_auth payloads a refcount. Take a payload reference while\nauthkey-\u003esem stabilizes the payload and revocation state. Hold that\nreference across the instantiate and reject paths. Drop the auth key\nowning reference from revoke and destroy.\n\n[jarkko: Replaced the first two paragraphs of text with an actual\n concurrency scenario.]"
}
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"title": "kernel: keys: Pin request_key_auth payload in instantiate paths",
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"status": "interim",
"title": "SUSE CVE CVE-2026-63823",
"url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-63823.json",
"version": "13"
}
}
}
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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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