# CVE-2026-73212: Server-side request forgery in coturn

> An authenticated attacker can bypass peer IP restrictions via IPv6 canonicalization flaws to perform SSRF and achieve remote code execution on the internal network.

- **Severity:** Medium 5.8 (`CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:N/SC:H/SI:H/SA:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 11 Aug 2026
- **Updated:** 11 Aug 2026
- **Also known as:** DEBIAN-CVE-2026-73212, GHSA-2x4g-wx24-48m4, UBUNTU-CVE-2026-73212

## What is CVE-2026-73212?

CVE-2026-73212 is a medium-severity server-side request forgery vulnerability in coturn, published on 11 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Coturn is a free open source implementation of TURN and STUN Server. Prior to 4.13.1, good_peer_addr() in src/server/ns_turn_server.c uses ioa_addr_in_range() in src/client/ns_turn_ioaddr.c without canonicalizing IPv4-compatible, 6to4, and 64:ff9b::/96 NAT64 address forms, allowing an authenticated RFC 6062 TCP CONNECT relay client to bypass an IPv4 denied-peer-ip range when the Coturn host has a useful translation route. This issue is fixed in version 4.13.1.

Weakness: CWE-918 (Server-Side Request Forgery), CWE-284 (Improper Access Control)

## Which versions are affected by CVE-2026-73212?


## How do I fix CVE-2026-73212?

Upgrade to a fixed version.

## Is CVE-2026-73212 being exploited?

There is no known exploitation of CVE-2026-73212 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-73212 and fix it if it is affected.

What it is: CVE-2026-73212 is a medium-severity server-side request forgery vulnerability in coturn, published on 11 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-73212 in the wild and no public exploit code.

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-2026-73212/ (Markdown: https://insights.sbomify.com/CVE-2026-73212/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-73212
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-73212
- OSV: https://osv.dev/vulnerability/CVE-2026-73212

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-73212/
Summaries are generated and may contain mistakes; the official description above is the record.