# CVE-2025-68313: x86/CPU/AMD: Add RDSEED fix for Zen5

> AMD Zen5 CPUs may return zero from RDSEED instructions, compromising random number generation quality for security-sensitive operations.

- **Severity:** High 7.1 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 16 Dec 2025
- **Updated:** 15 Oct 2026
- **Also known as:** AZL-72628, BELL-CVE-2025-68313, DEBIAN-CVE-2025-68313, GHSA-hccf-2qv6-3rfj, ROOT-OS-DEBIAN-13-CVE-2025-68313, ROOT-OS-UBUNTU-2204-CVE-2025-68313, ROOT-OS-UBUNTU-2404-CVE-2025-68313, UBUNTU-CVE-2025-68313

## What is CVE-2025-68313?

CVE-2025-68313 is a high-severity vulnerability in Linux, published on 16 Dec 2025. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

In the Linux kernel, the following vulnerability has been resolved:

x86/CPU/AMD: Add RDSEED fix for Zen5

There's an issue with RDSEED's 16-bit and 32-bit register output
variants on Zen5 which return a random value of 0 "at a rate inconsistent
with randomness while incorrectly signaling success (CF=1)". Search the
web for AMD-SB-7055 for more detail.

Add a fix glue which checks microcode revisions.

  [ bp: Add microcode revisions checking, rewrite. ]

## Which versions are affected by CVE-2025-68313?


## How do I fix CVE-2025-68313?

Apply the vendor's patch.

## Is CVE-2025-68313 being exploited?

There is no known exploitation of CVE-2025-68313 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-68313 and fix it if it is affected.

What it is: CVE-2025-68313 is a high-severity vulnerability in Linux, published on 16 Dec 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2025-68313 in the wild and no public exploit code.

Affected product: Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2025-68313/ (Markdown: https://insights.sbomify.com/CVE-2025-68313/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-68313
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-68313
- OSV: https://osv.dev/vulnerability/CVE-2025-68313

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-68313/
Summaries are generated and may contain mistakes; the official description above is the record.