CVE-2026-25949
Traefik: TCP readTimeout bypass via STARTTLS on Postgres
No exploitation reported by the sources we read.
- Published2026-02-12
- WeaknessCWE-400 · CWE-770
Am I affected?
Debian, Ubuntu or Red Hat sometimes backport a fix without changing the upstream version number: such a version reads « to verify », never « affected ».With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.
Description
Traefik is an HTTP reverse proxy and load balancer. Prior to 3.6.8, there is a potential vulnerability in Traefik managing STARTTLS requests. An unauthenticated client can bypass Traefik entrypoint respondingTimeouts.readTimeout by sending the 8-byte Postgres SSLRequest (STARTTLS) prelude and then stalling, causing connections to remain open indefinitely, leading to a denial of service. This vulnerability is fixed in 3.6.8.
Timeline
dates in UTC- 2026-02-1220:16CVE publishedNVD
Observed activity
isMalicious corpus · updated 2026-10-23 21:37 UTCBlock these indicators
- Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2026-25949?format=txt
- CSV export: https://api.ismalicious.com/edl/cve/CVE-2026-25949?format=csv
- TAXII collection of exploited CVEs
- The EDL and CSV take an API key on the Pro plan.
Versions per branch
OSV · NVD| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| — | all versions | no fix published | OSV |
| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| — | all versions | no fix published | OSV |
| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 3.6 | < 3.6.8 | 3.6.8 | NVD · OSV |
as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.
Distribution builds and vendor advisories
Packages from OSV.dev and products from the vendors' CSAF advisories.
version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.
Vendor advisories
github.com/traefik/traefik: Traefik: Denial of Service via stalled STARTTLS requests
Red Hat Security Advisory: Red Hat OpenShift Dev Spaces 3.27.0 Release.
Fix
- Vendor fix Red Hat Product Security RHSA-2026:6192 · 4 productsBefore applying this update, make sure all previously released errata relevant to your system have been applied. For details on how to apply this update, refer to: https://access.redhat.com/articles/11258
Advisories and patches
- github.comPatch
- github.comRelease Notes
- github.comPatch · Vendor Advisory
Detection
- Nuclei template
- none so far ProjectDiscovery
- Exploit-DB
- no entry Exploit-DB
- Proof-of-concept repositories
- none listed PoC-in-GitHub
Sources
Technical details
- CVSS v3 Vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Published
- 2026-02-12
- Last Modified
- 2026-07-15
- NVD status
- Modified
Frequently asked questions
What is CVE-2026-25949?
Is CVE-2026-25949 actively exploited?
What is the CVSS score for CVE-2026-25949?
Running traefik/traefik? Hear about its next vulnerability
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Related vulnerabilities
Same product first, then the same vendor advisory and the same publication week.