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{"bugzilla": {"description": "github.com/traefik/traefik: Traefik: Username enumeration via timing side-channel in BasicAuth middleware", "id": "2464238", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2464238"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.3", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N", "status": "draft"}, "cwe": "CWE-208", "details": ["A flaw was found in Traefik. A remote attacker can exploit a timing side-channel vulnerability in Traefik's BasicAuth middleware. This flaw allows an attacker to enumerate valid usernames by observing differences in authentication response times. The vulnerability arises because a constant-time comparison, intended to prevent such attacks, short-circuits, revealing whether a username exists."], "mitigation": {"lang": "en:us", "value": "To mitigate this issue, restrict network access to Traefik instances that utilize the BasicAuth middleware. Implement firewall rules or network access controls to limit connections to trusted networks or clients only. This reduces the exposure to remote attackers attempting username enumeration. Always ensure that any changes to network configurations are thoroughly tested to prevent service disruption. A service reload or restart may be required for changes to take effect."}, "name": "CVE-2026-41263", "package_state": [{"cpe": "cpe:/a:redhat:openshift_devspaces:3", "fix_state": "Fix deferred", "package_name": "devspaces/traefik-rhel9", "product_name": "Red Hat OpenShift Dev Spaces"}], "public_date": "2026-04-30T20:39:49Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-41263\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-41263\nhttps://github.com/traefik/traefik/releases/tag/v2.11.43\nhttps://github.com/traefik/traefik/releases/tag/v3.6.14\nhttps://github.com/traefik/traefik/releases/tag/v3.7.0-rc.2\nhttps://github.com/traefik/traefik/security/advisories/GHSA-6x2q-h3cr-8j2h"], "threat_severity": "Moderate"}