{"cve":"CVE-2025-48865","nvd":{"published":"2025-05-30T07:15:23.940","modified":"2026-06-17T09:30:24.323","status":"Analyzed","description":"Fabio is an HTTP(S) and TCP router for deploying applications managed by consul. Prior to version 1.6.6, Fabio allows clients to remove X-Forwarded headers (except X-Forwarded-For) due to a vulnerability in how it processes hop-by-hop headers. Fabio adds HTTP headers like X-Forwarded-Host and X-Forwarded-Port when routing requests to backend applications. Since the receiving application should trust these headers, allowing HTTP clients to remove or modify them creates potential security vulnerabilities. Some of these custom headers can be removed and, in certain cases, manipulated. The attack relies on the behavior that headers can be defined as hop-by-hop via the HTTP Connection header. This issue has been patched in version 1.6.6.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","score":9.1},"cwes":["CWE-345","CWE-348"],"references":["https://github.com/fabiolb/fabio/commit/fdaf1e966162e9dd3b347ffdd0647b39dc71a1a3","https://github.com/fabiolb/fabio/releases/tag/v1.6.6","https://github.com/fabiolb/fabio/security/advisories/GHSA-q7p4-7xjv-j3wf","https://github.com/fabiolb/fabio/security/advisories/GHSA-q7p4-7xjv-j3wf"],"products":["fabiolb:fabio"],"source":"nvd","synced_at":"2026-10-19T22:02:23.998251710+00:00"},"epss":{"cve":"CVE-2025-48865","score":0.00466,"percentile":0.40386,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-q7p4-7xjv-j3wf","url":"https://osv.dev/vulnerability/GHSA-q7p4-7xjv-j3wf","summary":"Fabio allows HTTP clients to manipulate custom headers it adds","modified":"2026-09-10T03:50:24.674490827Z","packages":[{"ecosystem":"Go","name":"github.com/fabiolb/fabio","purl":"pkg:golang/github.com/fabiolb/fabio","ranges":["<1.6.6"],"fixed":["1.6.6"]}]},{"id":"GO-2025-3722","url":"https://osv.dev/vulnerability/GO-2025-3722","summary":"Fabio allows HTTP clients to manipulate custom headers it adds in github.com/fabiolb/fabio","modified":"2025-06-03T17:58:44.192155Z","packages":[{"ecosystem":"Go","name":"github.com/fabiolb/fabio","purl":"pkg:golang/github.com/fabiolb/fabio","ranges":["<1.6.6"],"fixed":["1.6.6"]}]}],"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."]}