CVE-2026-74578: Linux kernel · crypto: algif_skcipher – force synchronous processing on trees without ctx->state
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.1 High · fixed in 5.15.0-1117.124~20.04.1 : patch Linux kernel soon.
Data as of 26 Oct 2026, 13:47 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 9% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 5.15.0-1117.124~20.04.1, 5.15.0-1123.132~20.04.1, 5.15.0-1122.131~20.04.1 +28
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:NExploitation evidence
Disclosed: evidence found.
CVE published 16 Aug 2026
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 to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gkepkg:deb/ubuntu/linux-gke?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A patch is available and should be applied. The fix forces synchronous processing of cryptographic requests in the affected code path, eliminating the IV race condition. Users should update to the fixed linux-azure kernel versions listed in the advisory. No additional mitigation is required as the vulnerability is resolved by this official fix.
Description
A vulnerability in the Linux kernel's crypto subsystem (algif_skcipher) allowed asynchronous processing of cryptographic requests with a race condition on the initialization vector (IV). This could enable an unprivileged local attacker to recover plaintext by causing IV reuse in CTR/stream cipher modes. The issue was fixed by forcing synchronous processing of these requests, eliminating the race condition. The fix is included in specific linux-azure kernel versions.
References
- nvd.nist.gov/vuln/detail/CVE-2026-74578 (opens in a new tab)
- git.kernel.org/stable/c/60eafc7b08c6689ea3ad39eff8d97aefc8a087c7 (opens in a new tab)
- git.kernel.org/stable/c/73dd3bf704ca6c20639de70c08e9a10bee904a95 (opens in a new tab)
- git.kernel.org/stable/c/7b91e51d0eb7cbb07f7f086f9176bd93dbbc85dd (opens in a new tab)
- git.kernel.org/stable/c/b05defc41b27c7d0c05c45f67bf5b91c28f93669 (opens in a new tab)
- git.kernel.org/stable/c/bf09b0be8e851f050e98da702d247c14d81b591a (opens in a new tab)
- git.kernel.org/stable/c/d7860b682da55433b5da0591b0e4c1982ecd2689 (opens in a new tab)
- git.kernel.org/stable/c/f1a87ca0843d74482402a206ea2dfb315ee9acbd (opens in a new tab)
- git.kernel.org/stable/c/fcc77d33a34cf271702e8daafb6c593e4626776d (opens in a new tab)
- ubuntu.com/security/CVE-2026-74578 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-74578 (opens in a new tab)
- git.kernel.org/linus/fcc77d33a34cf271702e8daafb6c593e4626776d (opens in a new tab)
- ubuntu.com/security/notices/USN-8876-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8878-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8879-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8877-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8875-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8886-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8875-2 (opens in a new tab)