CVE-2026-64208: Linux kernel · crypto/krb5, rxrpc: Fix lack of pre-decrypt/pre-verify length checks
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.5 High · fixed in 7.0.0-28.28~24.04.1 : patch Linux kernel soon.
Data as of 26 Oct 2026, 17:16 UTC
- EPSS
- 0.6% chance of exploitation in 30 days – higher than 48% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 7.0.0-28.28~24.04.1, 7.0.0-1016.16~24.04.1, 7.0.0-28.28 +12
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 27 Jul 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.
Patches and advisories
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 to affected linux-hwe-edge kernel versions. The vendor advisory from Ubuntu confirms that this issue has been fixed in updated kernel releases. Users should update to the fixed kernel versions to mitigate this vulnerability.
Description
A vulnerability in the Linux kernel's crypto/krb5 and rxrpc subsystems was fixed by adding pre-decrypt and pre-verify length checks. This change improves validation of DATA packets secured with RxGK, preventing potential issues caused by lack of length checks before decryption or verification. The vulnerability affects multiple versions of the linux-hwe-edge kernel. The issue has been addressed in official updates.
References
- ubuntu.com/security/CVE-2026-64208 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-64208 (opens in a new tab)
- git.kernel.org/linus/2b50aceafe6606ea52ed42aadd1b4d44a188aade (opens in a new tab)
- git.kernel.org/stable/c/2b50aceafe6606ea52ed42aadd1b4d44a188aade (opens in a new tab)
- git.kernel.org/stable/c/585f9f6aef5c4542ac9d6ec45cd7dbc7df9af3ff (opens in a new tab)
- git.kernel.org/stable/c/9217017f4bce53dddb8d547837f1f707045d64ad (opens in a new tab)
- ubuntu.com/security/notices/USN-8618-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8663-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8664-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8728-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8728-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8728-3 (opens in a new tab)