# CVE-2023-20521: Race condition in 1st Gen AMD EPYC™ Processors

> An attacker with physical access can exploit a race condition in the ASP Bootloader to tamper with SPI ROM records, causing data leakage or denial of service.

- **Severity:** Low 3.3 (`CVSS:3.1/AV:P/AC:H/PR:H/UI:N/S:C/C:L/I:N/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 14 Nov 2023
- **Updated:** 2 Aug 2024
- **Also known as:** GHSA-7r55-mp9r-c8pj

## What is CVE-2023-20521?

CVE-2023-20521 is a low-severity vulnerability in Amd Epyc 7232p Firmware, published on 14 Nov 2023. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

TOCTOU in the ASP Bootloader may allow an attacker with physical access to tamper with SPI ROM records after memory content verification, potentially leading to loss of confidentiality or a denial of service.

Weakness: CWE-367 (Time-of-check Time-of-use (TOCTOU) Race Condition)

## Which versions are affected by CVE-2023-20521?

It affects 93 products.


Products: Amd Amd 3015ce Firmware, Amd Amd 3015e Firmware, Amd Athlon Gold 3150g Firmware, Amd Athlon Gold Pro 3150g Firmware, Amd Athlon Gold Pro 3150ge Firmware, Amd Athlon Pro 300ge Firmware, Amd Epyc 7001 Firmware, Amd Epyc 7203 Firmware, Amd Epyc 7203p Firmware, Amd Epyc 7232p Firmware, Amd Epyc 7251 Firmware, Amd Epyc 7252 Firmware, Amd Epyc 7261 Firmware, Amd Epyc 7262 Firmware, Amd Epyc 7272 Firmware, Amd Epyc 7281 Firmware, Amd Epyc 7282 Firmware, Amd Epyc 72f3 Firmware, Amd Epyc 7301 Firmware, Amd Epyc 7302 Firmware and 73 more.

## How do I fix CVE-2023-20521?

Apply the vendor's patch.

## Is CVE-2023-20521 being exploited?

There is no known exploitation of CVE-2023-20521 in the wild and no public exploit code.

## Other vulnerabilities in Amd Epyc 7232p Firmware

- [CVE-2021-26365](https://insights.sbomify.com/CVE-2021-26365/): Information disclosure in Athlon™ 3000 Series Mobile Processors with Radeon™ Graphics “Pollock” (high 8.2)
- [CVE-2020-12930](https://insights.sbomify.com/CVE-2020-12930/): Privilege escalation in AMD Radeon RX 5000 Series & PRO W5000 Series (high 7.8)
- [CVE-2020-12931](https://insights.sbomify.com/CVE-2020-12931/): Privilege escalation in AMD Radeon RX 5000 Series & PRO W5000 Series (high 7.8)
- [CVE-2021-26392](https://insights.sbomify.com/CVE-2021-26392/): Memory corruption in AMD Radeon RX 5000 Series & PRO W5000 Series (high 7.8)
- [CVE-2021-26354](https://insights.sbomify.com/CVE-2021-26354/): Memory corruption in 2nd Gen AMD EPYC™ Processors (medium 5.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-20521 and fix it if it is affected.

What it is: CVE-2023-20521 is a low-severity vulnerability in Amd Epyc 7232p Firmware, published on 14 Nov 2023. 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-2023-20521 in the wild and no public exploit code.

Affected product: Amd Epyc 7232p Firmware. 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-2023-20521/ (Markdown: https://insights.sbomify.com/CVE-2023-20521/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-20521
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-20521
- OSV: https://osv.dev/vulnerability/CVE-2023-20521

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-20521/
Summaries are generated and may contain mistakes; the official description above is the record.