CVE-2026-32595Traefik: BasicAuth Middleware Timing Attack Allows Username Enumeration
- 6.3MediumCVSS base score
- 0.40%Exploitation in 30 daysEPSS · top 65% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
Traefik is an HTTP reverse proxy and load balancer. Versions 2.11.40 and below, 3.0.0-beta1 through 3.6.11, and 3.7.0-ea.1 comtain BasicAuth middleware that allows username enumeration via a timing attack. When a submitted username exists, the middleware performs a bcrypt password comparison taking ~166ms. When the username does not exist, the response returns immediately in ~0.6ms. This ~298x timing difference is observable over the network and allows an unauthenticated attacker to reliably distinguish valid from invalid usernames. This issue is patched in versions 2.11.41, 3.6.11 and 3.7.0-ea.2.
Timeline
ID reserved
By GitHub_M
- 8 days later
· 8 days later
Published
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 4.0 | Medium6.3 | CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:N/SA:N |
| NVDNVD · Analyzed | 4.0 | Medium6.3 | CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
- EPSS (exploitation in 30 days)
- 0.40% · top 65% of all CVEs (13 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: Medium 6.3.
Affected products
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- Gogithub.com/traefik/traefikGHSA-g3hg-j4jv-cwfr (opens in a new tab)
- Gogithub.com/traefik/traefik/v2GHSA-g3hg-j4jv-cwfr (opens in a new tab)
- Gogithub.com/traefik/traefik/v3GHSA-g3hg-j4jv-cwfr (opens in a new tab)
References
References4
- https://github.com/traefik/traefik/security/advisories/GHSA-g3hg-j4jv-cwfr (opens in a new tab)x_refsource_CONFIRM
- https://github.com/traefik/traefik/releases/tag/v2.11.41 (opens in a new tab)x_refsource_MISC
- https://github.com/traefik/traefik/releases/tag/v3.6.11 (opens in a new tab)x_refsource_MISC
- https://github.com/traefik/traefik/releases/tag/v3.7.0-ea.2 (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)
- EUVD EUVD-2026-13664 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-g3hg-j4jv-cwfr (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-32595)Record last updated .