# CVE-2026-68554: Security feature bypass in coturn

> On-path attackers can modify authenticated TURN requests by appending attributes after MESSAGE-INTEGRITY, bypassing integrity checks and altering server behavior.

- **Severity:** Low 2.3 (`CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 19 Aug 2026
- **Updated:** 20 Aug 2026
- **Also known as:** DEBIAN-CVE-2026-68554, GHSA-5538-7cxj-5jcc, UBUNTU-CVE-2026-68554

## What is CVE-2026-68554?

CVE-2026-68554 is a low-severity vulnerability in coturn, published on 19 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

Coturn is a free open source implementation of TURN and STUN Server. Prior to 4.15.0, an on-path attacker can append attributes after MESSAGE-INTEGRITY to an authenticated STUN request on plain UDP or TCP, adjust the STUN header length, and recompute the unkeyed FINGERPRINT while the original HMAC remains valid because it covers only the message prefix. Server-side parsing in src/server/ns_turn_server.c continues past MESSAGE-INTEGRITY through handle_turn_allocate(), handle_turn_create_permission(), handle_turn_refresh(), and handle_turn_command(), allowing trailing LIFETIME, XOR-PEER-ADDRESS, or ORIGIN attributes to override allocation lifetime, inject a permission, or bypass the origin check. TLS and DTLS deployments prevent this in-transit modification. This issue is fixed in version 4.15.0.

Weakness: CWE-924 (Improper Enforcement of Message Integrity During Transmission in a Communication Channel), CWE-345 (Insufficient Verification of Data Authenticity)

## Which versions are affected by CVE-2026-68554?


## How do I fix CVE-2026-68554?

Upgrade to a fixed version.

## Is CVE-2026-68554 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-68554 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-68554 and fix it if it is affected.

What it is: CVE-2026-68554 is a low-severity vulnerability in coturn, published on 19 Aug 2026. 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-2026-68554 exists.

Affected product: coturn. 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-2026-68554/ (Markdown: https://insights.sbomify.com/CVE-2026-68554/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-68554
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-68554
- OSV: https://osv.dev/vulnerability/CVE-2026-68554

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-68554/
Summaries are generated and may contain mistakes; the official description above is the record.