CVE-2025-69217
Coturn has unsafe nonce and relay port randomization due to weak random number generation.
- Published
- Updated
- Reserved
- Assigned by
- GitHub_M
Description
coturn is a free open source implementation of TURN and STUN Server. Versions 4.6.2r5 through 4.7.0-r4 have a bad random number generator for nonces and port randomization after refactoring. Additionally, random numbers aren't generated with openssl's RAND_bytes but libc's random() (if it's not running on Windows). When fetching about 50 sequential nonces (i.e., through sending 50 unauthenticated allocations requests) it is possible to completely reconstruct the current state of the random number generator, thereby predicting the next nonce. This allows authentication while spoofing IPs. An attacker can send authenticated messages without ever receiving the responses, including the nonce (requires knowledge of the credentials, which is e.g., often the case in IoT settings). Since the port randomization is deterministic given the pseudorandom seed, an attacker can exactly reconstruct the ports and, hence predict the randomization of the ports. If an attacker allocates a relay port, they know the current port, and they are able to predict the next relay port (at least if it is not used before). Commit 11fc465f4bba70bb0ad8aae17d6c4a63a29917d9 contains a fix.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | High7.7 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H |
| NVDNVD · Deferred | 3.1 | High7.7 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.41% · top 64% of all CVEs (6 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.7.
Weakness
Affected products
References (3)
- https://github.com/coturn/coturn/security/advisories/GHSA-fvj6-9jhg-9j84 (opens in a new tab)x_refsource_CONFIRM
- https://github.com/coturn/coturn/commit/11fc465f4bba70bb0ad8aae17d6c4a63a29917d9 (opens in a new tab)x_refsource_MISC
- https://github.com/coturn/coturn/commit/88ced471385869d7e7fbbc4766e78ef521b36af6 (opens in a new tab)x_refsource_MISC
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2025-69217)Record last updated .