# CVE-2021-41141: Missing release of locks in PJSIP

> Attackers can trigger a deadlock in PJSIP by causing errors that fail to release locks, leading to denial of service for users.

- **Severity:** Medium 5.9 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/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:** Not needed
- **Fix available:** Yes
- **Published:** 4 Jan 2022
- **Updated:** 23 Apr 2025
- **Also known as:** ALPINE-CVE-2021-41141, GHSA-8fmx-hqw7-6gmc, UBUNTU-CVE-2021-41141

## What is CVE-2021-41141?

CVE-2021-41141 is a medium-severity denial of service vulnerability in Debian Debian Linux, published on 4 Jan 2022. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

PJSIP is a free and open source multimedia communication library written in the C language implementing standard based protocols such as SIP, SDP, RTP, STUN, TURN, and ICE. In various parts of PJSIP, when error/failure occurs, it is found that the function returns without releasing the currently held locks. This could result in a system deadlock, which cause a denial of service for the users. No release has yet been made which contains the linked fix commit. All versions up to an including 2.11.1 are affected. Users may need to manually apply the patch.

Weakness: CWE-667 (Improper Locking)

## Which versions are affected by CVE-2021-41141?

It affects 2 products.


Products: Debian Debian Linux, Teluu Pjsip.

## How do I fix CVE-2021-41141?

Apply the vendor's patch.

## Is CVE-2021-41141 being exploited?

There is no known exploitation of CVE-2021-41141 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-2021-41141 and fix it if it is affected.

What it is: CVE-2021-41141 is a medium-severity denial of service vulnerability in Debian Debian Linux, published on 4 Jan 2022. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2021-41141 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-2021-41141/ (Markdown: https://insights.sbomify.com/CVE-2021-41141/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-41141
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-41141
- OSV: https://osv.dev/vulnerability/CVE-2021-41141

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-41141/
Summaries are generated and may contain mistakes; the official description above is the record.