CVE-2025-40182: Linux kernel · crypto: skcipher – Fix reqsize handling
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.8 High · fixed in 6.17.0-1011.11 : patch Linux kernel soon.
Data as of 26 Oct 2026, 12:55 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 4% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 6.17.0-1011.11, 6.17.0-1008.8~24.04.1, 6.17.0-1008.8 +1
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 12 Nov 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade Linux kernel to 6.17.0-1011.11, 6.17.0-1008.8~24.04.1, 6.17.0-1008.8 or 6.17.0-1007.7~24.04.1.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| linux-hwe-edge | Affected
| Fixed in
|
AI-suggested
A fix has been implemented in the Linux kernel to properly initialize the reqsize field in skcipher algorithms by adding the necessary set_reqsize calls during initialization. Users and administrators should apply the official Linux kernel updates that include this fix. Patch status is not explicitly confirmed in the provided data; therefore, check the vendor advisory or Linux kernel mailing lists for the latest remediation guidance.
Description
In the Linux kernel, the following vulnerability has been resolved: crypto: skcipher - Fix reqsize handling Commit afddce13ce81d ("crypto: api - Add reqsize to crypto_alg") introduced cra_reqsize field in crypto_alg struct to replace type specific reqsize fields. It looks like this was introduced specifically for ahash and acomp from the commit description as subsequent commits add necessary changes in these alg frameworks. However, this is being recommended for use in all crypto algs [1] instead of setting reqsize using crypto_*_set_reqsize(). Using cra_reqsize in skcipher algorithms, hence, causes memory corruptions and crashes as the underlying functions in the algorithm framework have not been updated to set the reqsize properly from cra_reqsize. [2] Add proper set_reqsize calls in the skcipher init function to properly initialize reqsize for these algorithms in the framework. [1]: https://lore.kernel.org/linux-crypto/aCL8BxpHr5OpT04k@gondor.apana.org.au/ [2]: https://gist.github.com/Pratham-T/24247446f1faf4b7843e4014d5089f6b
References
- nvd.nist.gov/vuln/detail/CVE-2025-40182 (opens in a new tab)
- git.kernel.org/stable/c/229c586b5e86979badb7cb0d38717b88a9e95ddd (opens in a new tab)
- git.kernel.org/stable/c/f041339d6b9a5a46437f0c48fc7279c92af7a513 (opens in a new tab)
- ubuntu.com/security/CVE-2025-40182 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2025-40182 (opens in a new tab)
- git.kernel.org/linus/229c586b5e86979badb7cb0d38717b88a9e95ddd (opens in a new tab)
- ubuntu.com/security/notices/USN-8029-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8030-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8029-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8048-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8029-3 (opens in a new tab)