# CVE-2025-29476: Memory corruption in n/a

> A buffer overflow in the C-Blosc2 library allows attackers to execute arbitrary code or cause denial of service via crafted compressed data.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 4 Apr 2025
- **Updated:** 7 Apr 2025
- **Also known as:** DEBIAN-CVE-2025-29476, GHSA-p53h-9vwh-rvvp, UBUNTU-CVE-2025-29476

## What is CVE-2025-29476?

CVE-2025-29476 is a medium-severity memory corruption vulnerability in n/a, published on 4 Apr 2025. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.

### Official description

Buffer Overflow vulnerability in compress_chunk_fuzzer with oss-fuzz on commit 16450518afddcb3139de627157208e49bfef6987 in c-blosc2 v.2.17.0 and before.

Weakness: CWE-120 (Buffer Copy without Checking Size of Input)

## Which versions are affected by CVE-2025-29476?


## How do I fix CVE-2025-29476?

Upgrade to a fixed version.

## Is CVE-2025-29476 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-29476 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-29476 and fix it if it is affected.

What it is: CVE-2025-29476 is a medium-severity memory corruption vulnerability in n/a, published on 4 Apr 2025. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-29476 exists.

Affected product: n/a. 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-2025-29476/ (Markdown: https://insights.sbomify.com/CVE-2025-29476/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-29476
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-29476
- OSV: https://osv.dev/vulnerability/CVE-2025-29476

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-29476/
Summaries are generated and may contain mistakes; the official description above is the record.