Revive Adserver up to 6.0.4 Setting format string

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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2.7$0-$5k0.00

Summaryinfo

A vulnerability identified as critical has been detected in Revive Adserver up to 6.0.4. This impacts an unknown function of the component Setting Handler. The manipulation leads to format string. This vulnerability is listed as CVE-2026-21640. The attack may be initiated remotely. There is no available exploit. It is suggested to install a patch to address this issue.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in Revive Adserver up to 6.0.4. This issue affects some unknown functionality of the component Setting Handler. The manipulation with an unknown input leads to a format string vulnerability. Using CWE to declare the problem leads to CWE-134. The product uses a function that accepts a format string as an argument, but the format string originates from an external source. Impacted is availability. The summary by CVE is:

HackerOne community member Faraz Ahmed (PakCyberbot) has reported a format string injection in the Revive Adserver settings. When specific character combinations are used in a setting, the admin user console could be disabled due to a fatal PHP error.

The advisory is shared at seclists.org. The identification of this vulnerability is CVE-2026-21640. The exploitation is known to be easy. The attack may be initiated remotely. Additional levels of successful authentication are necessary for exploitation. Neither technical details nor an exploit are publicly available.

Applying a patch is able to eliminate this problem. The bugfix is ready for download at github.com.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 2.7
VulDB Meta Temp Score: 2.7

VulDB Base Score: 2.7
VulDB Temp Score: 2.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 2.7
NVD Vector: 🔒

CNA Base Score: 2.7
CNA Vector: 🔒

CVSSv2info

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

Exploitinginfo

Class: Format string
CWE: CWE-134 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔒

Patch: github.com

Timelineinfo

01/15/2026 Advisory disclosed
01/15/2026 +0 days VulDB entry created
01/31/2026 +16 days VulDB entry last update

Sourcesinfo

Advisory: seclists.org
Status: Confirmed
Confirmation: 🔒

CVE: CVE-2026-21640 (🔒)
GCVE (CVE): GCVE-0-2026-21640
GCVE (VulDB): GCVE-100-341273

Entryinfo

Created: 01/15/2026 10:13
Updated: 01/31/2026 05:14
Changes: 01/15/2026 10:13 (53), 01/27/2026 06:14 (10), 01/31/2026 05:14 (10)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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