{"cve":"CVE-2026-68554","nvd":{"published":"2026-08-19T21:17:28.310","modified":"2026-10-26T10:10:00.140","status":"Deferred","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.","cvss_v4":{"vector":"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","score":2.3},"cvss_v3":null,"cwes":["CWE-345","CWE-924"],"references":["https://github.com/coturn/coturn/commit/ab762f334f511ea37ab4b703a47d5d683a5be978","https://github.com/coturn/coturn/releases/tag/4.15.0","https://github.com/coturn/coturn/security/advisories/GHSA-5538-7cxj-5jcc","https://github.com/coturn/coturn/security/advisories/GHSA-5538-7cxj-5jcc"],"products":[],"source":"nvd","synced_at":"2026-10-26T10:28:23.151169805+00:00"},"epss":{"cve":"CVE-2026-68554","score":0.00188,"percentile":0.08321,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}