# CVE-2025-46420: Libsoup: memory leak on soup_header_parse_quality_list() via soup-headers.c

> Attackers can cause memory exhaustion and denial of service by sending crafted HTTP headers with zero-quality values to applications using libsoup.

- **Severity:** Medium 6.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 24 Apr 2025
- **Updated:** 25 Jul 2026
- **Also known as:** AZL-61567, AZL-61615, DEBIAN-CVE-2025-46420, GHSA-pv37-78jj-hvqv, UBUNTU-CVE-2025-46420

## What is CVE-2025-46420?

CVE-2025-46420 is a medium-severity denial of service vulnerability in Red Hat Enterprise Linux 10, published on 24 Apr 2025. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

A flaw was found in libsoup. It is vulnerable to memory leaks in the soup_header_parse_quality_list() function when parsing a quality list that contains elements with all zeroes.

Weakness: CWE-401 (Missing Release of Memory after Effective Lifetime)

## Which versions are affected by CVE-2025-46420?


## How do I fix CVE-2025-46420?

Apply the vendor's patch.

## Is CVE-2025-46420 being exploited?

There is no known exploitation of CVE-2025-46420 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-46420 and fix it if it is affected.

What it is: CVE-2025-46420 is a medium-severity denial of service vulnerability in Red Hat Enterprise Linux 10, published on 24 Apr 2025. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2025-46420 in the wild and no public exploit code.

Affected product: Red Hat Enterprise Linux 10. 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-2025-46420/ (Markdown: https://insights.sbomify.com/CVE-2025-46420/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-46420
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-46420
- OSV: https://osv.dev/vulnerability/CVE-2025-46420

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-46420/
Summaries are generated and may contain mistakes; the official description above is the record.