{"id":"CVE-2026-54735","aliases":["GHSA-4p3g-4hcj-wpvx","GO-2026-6139"],"url":"https://o3.security/vulnerability/CVE-2026-54735","summary":"prebid-server's request forgery vulnerability allows for possible host environment data extraction","details":"Prebid Server is an open-source solution for running real-time advertising auctions in the cloud. Prior to version 4.4.0, certain bidder adapters in Prebid Server interpolate user-supplied parameters into outbound request URLs without properly validating host and subdomain values, allowing crafted bid request parameters to cause server-side requests to unintended destinations and potentially expose internal network services or sensitive server endpoints. This issue is fixed in version 4.4.0.","published":"2026-07-29T15:59:46.640Z","modified":"2026-09-09T18:26:41.610514587Z","cvss":{"score":10,"severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H"},"epss":{"score":0.00345,"percentile":0.27773,"asOf":"2026-09-12"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Go","name":"github.com/prebid/prebid-server/v4","fixedVersion":"4.4.0"},{"ecosystem":"Go","name":"github.com/prebid/prebid-server/v3","fixedVersion":null},{"ecosystem":"Go","name":"github.com/prebid/prebid-server/v2","fixedVersion":null},{"ecosystem":"Go","name":"github.com/prebid/prebid-server","fixedVersion":null}],"fix":{"url":"https://github.com/prebid/prebid-server/commit/494ac271cd4b5024df9123ef25ca3cff96390be3","label":"prebid/prebid-server@494ac27"},"references":[{"type":"WEB","url":"https://github.com/prebid/prebid-server/releases/tag/v4.4.0"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/54xxx/CVE-2026-54735.json"},{"type":"ADVISORY","url":"https://github.com/prebid/prebid-server/security/advisories/GHSA-4p3g-4hcj-wpvx"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-54735"},{"type":"FIX","url":"https://github.com/prebid/prebid-server/commit/494ac271cd4b5024df9123ef25ca3cff96390be3"},{"type":"FIX","url":"https://github.com/prebid/prebid-server/pull/4802"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-09-09T18:26:41.610514587Z"}}