# CVE-2020-25643: Memory corruption in kernel

> A memory corruption flaw in the Linux kernel HDLC_PPP module allows attackers to cause a system crash or denial of service.

- **Severity:** High 7.2 (`CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 6 Oct 2020
- **Updated:** 4 Aug 2024
- **Also known as:** DEBIAN-CVE-2020-25643, GHSA-vhhq-pmj4-x7gm, UBUNTU-CVE-2020-25643

## What is CVE-2020-25643?

CVE-2020-25643 is a high-severity memory corruption vulnerability in Debian Debian Linux, published on 6 Oct 2020. An attacker needs administrator access to exploit it, with no action from the victim.

### Official description

A flaw was found in the HDLC_PPP module of the Linux kernel in versions before 5.9-rc7. Memory corruption and a read overflow is caused by improper input validation in the ppp_cp_parse_cr function which can cause the system to crash or cause a denial of service. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2020-25643?

It affects 6 products.


Products: Debian Debian Linux, Linux kernel, Netapp H410c Firmware, Opensuse Leap, Redhat Enterprise Linux, Starwindsoftware Starwind Virtual San.

## How do I fix CVE-2020-25643?

Apply the vendor's patch.

## Is CVE-2020-25643 being exploited?

There is no known exploitation of CVE-2020-25643 in the wild and no public exploit code.

## Other vulnerabilities in Debian Debian Linux

- [CVE-2015-3306](https://insights.sbomify.com/CVE-2015-3306/): ProFTPD Improper Access Control (critical 10.0, exploited in the wild)
- [CVE-2025-49113](https://insights.sbomify.com/CVE-2025-49113/): RoundCube Webmail Deserialization of Untrusted Data (critical 9.9, exploited in the wild)
- [CVE-2026-24061](https://insights.sbomify.com/CVE-2026-24061/): GNU InetUtils Argument Injection (critical 9.8, exploited in the wild)
- [CVE-2025-39682](https://insights.sbomify.com/CVE-2025-39682/): Linux Kernel Improper Check for Unusual or Exceptional Conditions (critical 9.8, exploited in the wild)
- [CVE-2024-9680](https://insights.sbomify.com/CVE-2024-9680/): Mozilla Firefox Use-After-Free (critical 9.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-25643 and fix it if it is affected.

What it is: CVE-2020-25643 is a high-severity memory corruption vulnerability in Debian Debian Linux, published on 6 Oct 2020. An attacker needs administrator access to exploit it, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2020-25643 in the wild and no public exploit code.

Affected product: Debian Debian 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-2020-25643/ (Markdown: https://insights.sbomify.com/CVE-2020-25643/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-25643
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-25643
- OSV: https://osv.dev/vulnerability/CVE-2020-25643

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-25643/
Summaries are generated and may contain mistakes; the official description above is the record.