FastCGI fcgi2 up to 2.4.4 fcgiapp.c nameLen/valueLen integer overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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8.4$0-$5k0.00

Summaryinfo

A vulnerability was found in FastCGI fcgi2 up to 2.4.4 and classified as critical. Affected is an unknown function of the file fcgiapp.c. Such manipulation of the argument nameLen/valueLen leads to integer overflow. This vulnerability is uniquely identified as CVE-2025-23016. Local access is required to approach this attack. No exploit exists.

Detailsinfo

A vulnerability was found in FastCGI fcgi2 up to 2.4.4 and classified as critical. Affected by this issue is an unknown code of the file fcgiapp.c. The manipulation of the argument nameLen/valueLen with an unknown input leads to a integer overflow vulnerability. Using CWE to declare the problem leads to CWE-190. The product performs a calculation that can produce an integer overflow or wraparound, when the logic assumes that the resulting value will always be larger than the original value. This can introduce other weaknesses when the calculation is used for resource management or execution control. Impacted is confidentiality, integrity, and availability. CVE summarizes:

FastCGI fcgi2 (aka fcgi) 2.x through 2.4.4 has an integer overflow (and resultant heap-based buffer overflow) via crafted nameLen or valueLen values in data to the IPC socket. This occurs in ReadParams in fcgiapp.c.

The advisory is shared for download at github.com. This vulnerability is handled as CVE-2025-23016 since 01/10/2025. The exploitation is known to be easy. The attack needs to be approached locally. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 05/29/2025).

The vulnerability scanner Nessus provides a plugin with the ID 235315 (Azure Linux 3.0 Security Update: fcgi (CVE-2025-23016)), which helps to determine the existence of the flaw in a target environment.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the databases at Tenable (235315) and EUVD (EUVD-2025-3075). Once again VulDB remains the best source for vulnerability data.

Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.5
VulDB Meta Temp Score: 8.4

VulDB Base Score: 7.8
VulDB Temp Score: 7.5
VulDB Vector: 🔍
VulDB Reliability: 🔍

CNA Base Score: 9.3
CNA Vector (MITRE): 🔍

CVSSv2info

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

Exploitinginfo

Class: Integer overflow
CWE: CWE-190 / CWE-189
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 235315
Nessus Name: Azure Linux 3.0 Security Update: fcgi (CVE-2025-23016)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

01/10/2025 🔍
01/10/2025 +0 days 🔍
01/10/2025 +0 days 🔍
05/29/2025 +139 days 🔍

Sourcesinfo

Advisory: 67
Status: Not defined

CVE: CVE-2025-23016 (🔍)
GCVE (CVE): GCVE-0-2025-23016
GCVE (VulDB): GCVE-100-291092
EUVD: 🔍

Entryinfo

Created: 01/10/2025 14:09
Updated: 05/29/2025 06:19
Changes: 01/10/2025 14:09 (63), 04/24/2025 09:44 (1), 05/06/2025 17:59 (2), 05/29/2025 06:19 (1)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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