# CVE-2025-9396: ckolivas lrzip strtol_l.c __GI_____strtol_l_internal null pointer dereference

> A local attacker can cause a denial of service in lrzip via a null pointer dereference in the strtol_l_internal function.

- **Severity:** Medium 4.8 (`CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 24 Aug 2025
- **Updated:** 25 Aug 2025
- **Also known as:** DEBIAN-CVE-2025-9396, GHSA-7p5p-5c63-6f3w, UBUNTU-CVE-2025-9396

## What is CVE-2025-9396?

CVE-2025-9396 is a medium-severity vulnerability in ckolivas lrzip, published on 24 Aug 2025. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A security flaw has been discovered in ckolivas lrzip up to 0.651. This impacts the function __GI_____strtol_l_internal of the file strtol_l.c. Performing manipulation results in null pointer dereference. The attack is only possible with local access. The exploit has been released to the public and may be exploited.

Weakness: CWE-476 (NULL Pointer Dereference), CWE-404 (Improper Resource Shutdown or Release)

## Which versions are affected by CVE-2025-9396?

It affects 1 product.


Products: Ckolivas Lrzip.

## How do I fix CVE-2025-9396?

No fix published yet.

## Is CVE-2025-9396 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-9396 exists.

## Other vulnerabilities in ckolivas lrzip

- [CVE-2025-15570](https://insights.sbomify.com/CVE-2025-15570/): ckolivas lrzip stream.c lzma_decompress_buf use after free (medium 4.8)
- [CVE-2025-15571](https://insights.sbomify.com/CVE-2025-15571/): ckolivas lrzip stream.c ucompthread null pointer dereference (medium 4.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-9396 and fix it if it is affected.

What it is: CVE-2025-9396 is a medium-severity vulnerability in ckolivas lrzip, published on 24 Aug 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-9396 exists.

Affected product: ckolivas lrzip. 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-2025-9396/ (Markdown: https://insights.sbomify.com/CVE-2025-9396/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-9396
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-9396
- OSV: https://osv.dev/vulnerability/CVE-2025-9396

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-9396/
Summaries are generated and may contain mistakes; the official description above is the record.