CVE-2026-54735
CRITICALCVE-2026-54735 is a critical-severity (CVSS 10) Server-Side Request Forgery (SSRF) vulnerability. O3 Security confirms whether CVE-2026-54735 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
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…
Description
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.
Detection & mitigation playbook
VulnerabilityDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for the affected component. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Remediation status
No patched version of the affected component has shipped for CVE-2026-54735 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
Mitigate without a patch
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-54735 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-54735. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-54735 in your dependencies?
O3 detects CVE-2026-54735 across dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.