{"answers":{"affected":"11 open source packages ship an affected version, including github.com/traefik/traefik/v3, github.com/traefik/traefik and github.com/traefik/traefik/v2. It affects 1 product.","exploited":"There is no known exploitation of CVE-2026-41263 in the wild and no public exploit code.","fix":"Upgrade github.com/traefik/traefik/v3 to a fixed version for your release line: 3.6.14 or 3.7.0-rc.2.","what":"CVE-2026-41263 is a medium-severity vulnerability in Traefik Traefik, published on 30 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-41263 and fix it if it is affected.\n\nWhat it is: CVE-2026-41263 is a medium-severity vulnerability in Traefik Traefik, published on 30 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2026-41263 in the wild and no public exploit code.\n\nAffected packages and fixed versions:\n- github.com/traefik/traefik/v3 (Go): affected from 3.0.0-beta1; fixed in 3.6.14, 3.7.0-rc.2\n- github.com/traefik/traefik/v3 (Go): affected from 3.0.0-beta1; fixed in 3.6.14\n- github.com/traefik/traefik/v3 (Go): affected from 3.0.0-beta1; fixed in 3.6.14\n- github.com/traefik/traefik/v3 (Go): affected from 3.7.0-ea.1; fixed in 3.7.0-rc.2\n- github.com/traefik/traefik/v3 (Go): affected from 3.7.0-ea.1; fixed in 3.7.0-rc.2\n- github.com/traefik/traefik (Go): affected all versions; no fix listed\n- github.com/traefik/traefik (Go): affected all versions up to 1.7.34; no fix listed\n- github.com/traefik/traefik (Go): affected all versions up to 1.7.34; no fix listed\n- github.com/traefik/traefik/v2 (Go): affected all versions; fixed in 2.11.43\n- github.com/traefik/traefik/v2 (Go): affected all versions; fixed in 2.11.43\n- github.com/traefik/traefik/v2 (Go): affected all versions; fixed in 2.11.43\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2026-41263/ (Markdown: https://insights.sbomify.com/CVE-2026-41263/index.md)","id":"CVE-2026-41263","markdown":"https://insights.sbomify.com/CVE-2026-41263/index.md","name":"CVE-2026-41263","record":{"aliases":["CLEANSTART-2026-HD64585","GHSA-6x2q-h3cr-8j2h","GO-2026-5195","MINI-774v-rpcw-8ffc","MINI-7g79-rmjr-qfx4","MINI-f5q6-jfx8-m78r"],"analysis":{"component_type":"server_software","fix_type":"upgrade","impacts":["data_read"],"network_reachable":"yes","non_default_config":false,"product_category":"HTTP reverse proxy","requires_auth":"none","summary":"Attackers can enumerate valid usernames in Traefik's BasicAuth middleware by measuring response time differences due to a timing side-channel flaw.","user_interaction":"not_required","vuln_class":"information_disclosure"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[{"product":"traefik","vendor":"traefik"}],"cvss":{"score":6.3,"severity":"medium","source":"cna","vector":"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","version":"4.0"},"cwes":[{"id":"CWE-208","name":"Observable Timing Discrepancy"}],"description":"Traefik is an HTTP reverse proxy and load balancer. Prior to versions 2.11.43, 3.6.14, and 3.7.0-rc.2, there is a timing side-channel vulnerability in Traefik's BasicAuth middleware that allows an attacker to enumerate valid usernames through response-time differences. The variable intended to hold a constant-time fallback secret always resolves to an empty string, causing the constant-time comparison to short-circuit in microseconds rather than performing a full bcrypt evaluation. This restores the original timing oracle and makes it possible to distinguish existing users from non-existing ones by measuring authentication response times. This issue has been patched in versions 2.11.43, 3.6.14, and 3.7.0-rc.2.","ecosystems":["Go"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":true,"headline":"Traefik: BasicAuth middleware: timing side-channel vulnerability","id":"CVE-2026-41263","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"Go","product":"traefik:traefik","products":["traefik:traefik"],"type":"information_disclosure","year":"2026"},"n_packages":11,"n_references":4,"next":{"headline":"Flowise: CSV Agent Prompt Injection Remote Code Execution Vulnerability","id":"CVE-2026-41264"},"packages":[{"ecosystem":"Go","fixed":[],"introduced":["0"],"last_affected":[],"package":"github.com/traefik/traefik","purl":"pkg:golang/github.com/traefik/traefik","source":"GO-2026-5195"},{"ecosystem":"Go","fixed":[],"introduced":["0"],"last_affected":["1.7.34"],"package":"github.com/traefik/traefik","purl":null,"source":"GHSA-6x2q-h3cr-8j2h"},{"ecosystem":"Go","fixed":[],"introduced":["0"],"last_affected":["1.7.34"],"package":"github.com/traefik/traefik","purl":"pkg:golang/github.com/traefik/traefik","source":"GHSA-6x2q-h3cr-8j2h"},{"ecosystem":"Go","fixed":["2.11.43"],"introduced":["0"],"last_affected":[],"package":"github.com/traefik/traefik/v2","purl":null,"source":"GHSA-6x2q-h3cr-8j2h"},{"ecosystem":"Go","fixed":["2.11.43"],"introduced":["0"],"last_affected":[],"package":"github.com/traefik/traefik/v2","purl":"pkg:golang/github.com/traefik/traefik/v2","source":"GHSA-6x2q-h3cr-8j2h"},{"ecosystem":"Go","fixed":["2.11.43"],"introduced":["0"],"last_affected":[],"package":"github.com/traefik/traefik/v2","purl":"pkg:golang/github.com/traefik/traefik/v2","source":"GO-2026-5195"},{"ecosystem":"Go","fixed":["3.6.14","3.7.0-rc.2"],"introduced":["3.0.0-beta1","3.7.0-ea.1"],"last_affected":[],"package":"github.com/traefik/traefik/v3","purl":"pkg:golang/github.com/traefik/traefik/v3","source":"GO-2026-5195"},{"ecosystem":"Go","fixed":["3.6.14"],"introduced":["3.0.0-beta1"],"last_affected":[],"package":"github.com/traefik/traefik/v3","purl":null,"source":"GHSA-6x2q-h3cr-8j2h"},{"ecosystem":"Go","fixed":["3.6.14"],"introduced":["3.0.0-beta1"],"last_affected":[],"package":"github.com/traefik/traefik/v3","purl":"pkg:golang/github.com/traefik/traefik/v3","source":"GHSA-6x2q-h3cr-8j2h"},{"ecosystem":"Go","fixed":["3.7.0-rc.2"],"introduced":["3.7.0-ea.1"],"last_affected":[],"package":"github.com/traefik/traefik/v3","purl":null,"source":"GHSA-6x2q-h3cr-8j2h"},{"ecosystem":"Go","fixed":["3.7.0-rc.2"],"introduced":["3.7.0-ea.1"],"last_affected":[],"package":"github.com/traefik/traefik/v3","purl":"pkg:golang/github.com/traefik/traefik/v3","source":"GHSA-6x2q-h3cr-8j2h"}],"prev":{"headline":"Fleet: Cross-Team Policy Data Exposure via Global Policy Read Endpoint","id":"CVE-2026-41262"},"products":["traefik"],"published":"2026-04-30","related":[{"cvss_score":9.8,"headline":"HTTP client can remove the X-Forwarded headers in Traefik","id":"CVE-2024-45410","kev_date_added":null,"published":"2024-09-19"},{"cvss_score":9.3,"headline":"Traefik v3.7.0 Authentication Bypass via from-to-www-redirect","id":"CVE-2026-88877","kev_date_added":null,"published":"2026-09-10"},{"cvss_score":9.3,"headline":"Traefik before v2.11.55 and v3.0.0 through v3.7.10 Authentication Bypass via digestAuth","id":"CVE-2026-85595","kev_date_added":null,"published":"2026-09-04"},{"cvss_score":9.1,"headline":"Traefik HTTP/3 Backend NTLM Connection Reuse","id":"CVE-2026-88007","kev_date_added":null,"published":"2026-09-10"},{"cvss_score":8.8,"headline":"Traefik: Rootless HTTP/1 request-target routes as \"/\" but is forwarded verbatim, bypassing path-scoped routing, middleware guards and access logging","id":"CVE-2026-88009","kev_date_added":null,"published":"2026-09-10"},{"cvss_score":8.8,"headline":"Traefik has a possible vulnerability with the path matchers","id":"CVE-2025-32431","kev_date_added":null,"published":"2025-04-21"},{"cvss_score":8.2,"headline":"Traefik v3.7 Authentication Bypass via TLS Option Conflict","id":"CVE-2026-85596","kev_date_added":null,"published":"2026-09-04"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"GitHub Advisory Database","prefix":"GHSA"},{"class":"attribution","licence":"CC BY 4.0","name":"Go Vulnerability Database","prefix":"GO"},{"class":"attribution","licence":"US public information, NVD API terms","name":"NVD"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-05-01","vendors":["traefik"]},"summary":"Attackers can enumerate valid usernames in Traefik's BasicAuth middleware by measuring response time differences due to a timing side-channel flaw.","url":"https://insights.sbomify.com/CVE-2026-41263/"}