Prebid Server up to 4.3.x Bidder Adapters server-side request forgery

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.0$0-$5k2.16

Summaryinfo

A vulnerability classified as critical was found in Prebid Server up to 4.3.x. Impacted is an unknown function of the component Bidder Adapters. Executing a manipulation can lead to server-side request forgery. This vulnerability is tracked as CVE-2026-54735. The attack can be launched remotely. No exploit exists.

Detailsinfo

A vulnerability classified as critical was found in Prebid Server up to 4.3.x. This vulnerability affects an unknown function of the component Bidder Adapters. The manipulation with an unknown input leads to a server-side request forgery vulnerability. The CWE definition for the vulnerability is CWE-918. The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

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.

The advisory is available at github.com. This vulnerability was named CVE-2026-54735 since 06/16/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. The technical details are unknown and an exploit is not available.

Upgrading to version 4.4.0 eliminates this vulnerability.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.3
VulDB Meta Temp Score: 7.0

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Server-side request forgery
CWE: CWE-918
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Server 4.4.0

Timelineinfo

06/16/2026 CVE reserved
07/29/2026 +43 days Advisory disclosed
07/29/2026 +0 days VulDB entry created
07/29/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-54735 (🔒)
GCVE (CVE): GCVE-0-2026-54735
GCVE (VulDB): GCVE-100-384202

Entryinfo

Created: 07/29/2026 18:30
Changes: 07/29/2026 18:30 (55)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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