CVE-2026-68453: Linux kernel · s390/zcrypt: Fix buffer over-read in cca_cipher2protkey
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.1 High : upgrade to 6.8.0-1036.39 soon.
Data as of 28 Oct 2026, 05:11 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 5% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 6.8.0-1036.39
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 13 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 the Ubuntu linux-nvidia-tegra package to 6.8.0-1036.39.
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. The vulnerability is fixed in Linux kernel version 6.8.0-1036.39. Users should update to this version or later to remediate the issue. No additional mitigation steps are indicated by the vendor advisory.
Description
A buffer over-read vulnerability in the s390/zcrypt component of the Linux kernel was fixed by adding validation of key buffer sizes and token length fields. Improper validation allowed attackers to cause buffer over-reads or under-runs, potentially leading to kernel crashes or memory exposure. This flaw affects multiple Linux kernel versions and has been addressed in version 6.8.0-1036.39.
References
- ubuntu.com/security/CVE-2026-68453 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-68453 (opens in a new tab)
- git.kernel.org/stable/c/3b2abee2a678607ae27975bc6833785c2002df43 (opens in a new tab)
- git.kernel.org/stable/c/a57fd7fcdb63e2d5ceac78bbe825ec986062a9da (opens in a new tab)
- git.kernel.org/stable/c/36b230835b8a008266aad22168ca52afacc8a58d (opens in a new tab)
- ubuntu.com/security/notices/USN-8886-1 (opens in a new tab)