{"cve":"CVE-2026-26999","nvd":{"published":"2026-03-05T19:16:05.323","modified":"2026-07-15T02:19:02.967","status":"Modified","description":"Traefik is an HTTP reverse proxy and load balancer. Prior to versions 2.11.38 and 3.6.9, there is a potential vulnerability in Traefik managing TLS handshake on TCP routers. When Traefik processes a TLS connection on a TCP router, the read deadline used to bound protocol sniffing is cleared before the TLS handshake is completed. When a TLS handshake read error occurs, the code attempts a second handshake with different connection parameters, silently ignoring the initial error. A remote unauthenticated client can exploit this by sending an incomplete TLS record and stopping further data transmission, causing the TLS handshake to stall indefinitely and holding connections open. By opening many such stalled connections in parallel, an attacker can exhaust file descriptors and goroutines, degrading availability of all services on the affected entrypoint. This issue has been patched in versions 2.11.38 and 3.6.9.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":["CWE-400","CWE-772"],"references":["https://github.com/traefik/traefik/releases/tag/v2.11.38","https://github.com/traefik/traefik/releases/tag/v3.6.9","https://github.com/traefik/traefik/security/advisories/GHSA-xw98-5q62-jx94","https://access.redhat.com/errata/RHSA-2026:10175","https://access.redhat.com/security/cve/CVE-2026-26999"],"products":["traefik:traefik"],"source":"nvd","synced_at":"2026-10-19T22:25:53.701907451+00:00"},"epss":{"cve":"CVE-2026-26999","score":0.00612,"percentile":0.49327,"date":"2026-11-01"},"kev":null,"osv":[{"id":"GHSA-xw98-5q62-jx94","url":"https://osv.dev/vulnerability/GHSA-xw98-5q62-jx94","summary":"Traefik: tcp router clears read deadlines before tls forwarding, enabling stalled handshakes (Slowloris DOS)","modified":"2026-04-16T02:14:31.366308361Z","packages":[{"ecosystem":"Go","name":"github.com/traefik/traefik/v2","purl":"pkg:golang/github.com/traefik/traefik/v2","ranges":["<2.11.38"],"fixed":["2.11.38"]},{"ecosystem":"Go","name":"github.com/traefik/traefik/v3","purl":"pkg:golang/github.com/traefik/traefik/v3","ranges":["<3.6.9"],"fixed":["3.6.9"]}]},{"id":"GO-2026-4594","url":"https://osv.dev/vulnerability/GO-2026-4594","summary":"Traefik: tcp router clears read deadlines before tls forwarding, enabling stalled handshakes (Slowloris DOS) in github.com/traefik/traefik","modified":"2026-04-16T02:14:29.697878015Z","packages":[{"ecosystem":"Go","name":"github.com/traefik/traefik","purl":"pkg:golang/github.com/traefik/traefik","ranges":["all versions"],"fixed":[]},{"ecosystem":"Go","name":"github.com/traefik/traefik/v2","purl":"pkg:golang/github.com/traefik/traefik/v2","ranges":["<2.11.38"],"fixed":["2.11.38"]},{"ecosystem":"Go","name":"github.com/traefik/traefik/v3","purl":"pkg:golang/github.com/traefik/traefik/v3","ranges":["<3.6.9"],"fixed":["3.6.9"]}]}],"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."]}