by Kastro
Paper/Archive/CVE-2026-54735

CVE-2026-54735

prebid prebid-server — prebid-server's request forgery vulnerability allows for possible host environment data extraction

EPSS 0.6%CVSS 10.0
critical.is priorityof 100
40
CVSS 10.0 (CNA)10.0 / 10 × 3030.0Not in CISA KEV+300.0EPSS percentile 49.3.493 × 209.9No public exploit+100.0SSVC exploitation: none+100.0
Description · from the CVE record

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.

Affected

ProductAffectedFixed inSource
prebid-server< 4.4.0–CNA

Scores by source

GitHub_M (CNA)10.0CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
CISA ADPSSVCExploitation: none · Automatable: yes · Technical impact: total

References

refgithub.com/prebid/prebid-server/security/advisories/GHSA-4p3g-4hcj-wpvxrefgithub.com/prebid/prebid-server/pull/4802refgithub.com/prebid/prebid-server/commit/494ac271cd4b5024df9123ef25ca3cff96390be3refgithub.com/prebid/prebid-server/releases/tag/v4.4.0