CVE-2026-54735

critical · 10

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.

CVSS

0.3%

EPSS (exploit prob.)

28th

EPSS percentile

2026-07-29

Published

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

Weaknesses

CWE-918

Affected products

Vendor	Product	Affected versions
prebid	prebid_server	< 4.4.0

Check a specific version with /api/v1/cve/match.

References

https://github.com/prebid/prebid-server/commit/494ac271cd4b5024df9123ef25ca3cff96390be3
https://github.com/prebid/prebid-server/pull/4802
https://github.com/prebid/prebid-server/releases/tag/v4.4.0
https://github.com/prebid/prebid-server/security/advisories/GHSA-4p3g-4hcj-wpvx

Query this programmatically:

curl https://evil-db.io/api/v1/cve/CVE-2026-54735