{"id":"CVE-2026-66339","title":"Libsoup: libsoup: proxy credentials leak to destination server via proxy-authorization header in connect tunnels","summary":"A flaw was found in libsoup. After a CONNECT tunnel is established through an HTTP proxy, libsoup incorrectly attaches the Proxy-Authorization header to subsequent HTTPS requests sent through that tunnel to the destination server. This a…","severity":"medium","cvss":6.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N","cvssSource":"cna","cwe":["CWE-201"],"vendor":"Red Hat","product":"libsoup3","affected":["libsoup3 (all versions)","libsoup (all versions)","libsoup (all versions)","libsoup (all versions)","libsoup (all versions)"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-07-28T14:25:44.275356Z"},"published":"2026-07-24","updated":"2026-11-05","sourceUpdated":"2026-11-05T22:13:11.800Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-66339","references":[{"url":"https://access.redhat.com/security/cve/CVE-2026-66339"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2506951","label":"RHBZ#2506951"}],"tags":["cve.org"],"epss":0.00249,"epssPercentile":0.16301,"ingestedAt":"2026-11-05T23:41:31.952Z","slug":"CVE-2026-66339","body":"## Overview\n\nA flaw was found in libsoup. After a CONNECT tunnel is established through an HTTP proxy, libsoup incorrectly attaches the Proxy-Authorization header to subsequent HTTPS requests sent through that tunnel to the destination server. This allows the destination server to capture proxy credentials, leading to information disclosure.\n\n## Affected\n\n- `libsoup3 (all versions)`\n- `libsoup (all versions)`\n- `libsoup (all versions)`\n- `libsoup (all versions)`\n- `libsoup (all versions)`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":36,"depthScoreParts":{"impact":35.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}