---
id: CVE-2026-54735
aliases:
  - GHSA-4p3g-4hcj-wpvx
title: >-
  prebid-server's request forgery vulnerability allows for possible host
  environment data extraction
summary: >-
  prebid-server's request forgery vulnerability allows for possible host
  environment data extraction
severity: critical
cvss: 10
cwe:
  - CWE-918
vendor: prebid
product: github.com/prebid/prebid-server/v4
ecosystem: go
affected:
  - github.com/prebid/prebid-server/v4 < 4.4.0
  - github.com/prebid/prebid-server/v3 <= 3.30.0
  - github.com/prebid/prebid-server/v2 <= 2.32.0
  - github.com/prebid/prebid-server <= 0.275.0
patched:
  - github.com/prebid/prebid-server/v4 4.4.0
published: '2026-07-29'
updated: '2026-07-29'
source: GHSA
sourceUrl: 'https://github.com/advisories/GHSA-4p3g-4hcj-wpvx'
references:
  - url: >-
      https://github.com/prebid/prebid-server/security/advisories/GHSA-4p3g-4hcj-wpvx
  - url: 'https://github.com/prebid/prebid-server/pull/4802'
  - url: >-
      https://github.com/prebid/prebid-server/commit/494ac271cd4b5024df9123ef25ca3cff96390be3
  - url: 'https://github.com/prebid/prebid-server/releases/tag/v4.4.0'
  - url: 'https://github.com/advisories/GHSA-4p3g-4hcj-wpvx'
tags:
  - ghsa
  - go
ingestedAt: '2026-07-29T16:48:34.024Z'
epss: 0.00611
epssPercentile: 0.47051
---

## Overview

### Impact
Certain bidder adapters accept user-supplied parameters that are interpolated into outbound request URLs. Without proper input validation, a malicious actor could craft bid request parameters that cause the server to send HTTP requests to unintended destinations, potentially exposing internal network services or sensitive server endpoints to unauthorized access.

### Patches
Patched in [v4.4.0](https://github.com/prebid/prebid-server/releases/tag/v4.4.0)

### Workarounds
If one is unable to update, please make sure that the affected bidder adapters are disabled.

## Affected packages

- `github.com/prebid/prebid-server/v4 < 4.4.0`
- `github.com/prebid/prebid-server/v3 <= 3.30.0`
- `github.com/prebid/prebid-server/v2 <= 2.32.0`
- `github.com/prebid/prebid-server <= 0.275.0`

## Remediation

Upgrade to a patched release:

- `github.com/prebid/prebid-server/v4 4.4.0`