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TI-2025-16828 Aliases CVE-2025-23016GHSA-9825-56cx-cfg6

Integer overflow in FastCGI fcgi

Priority HIGH 75CWE-190Published · Updated

Key facts

Attack vector
Local
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-190 and the CVSS impact.

Summary

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00613 49th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
FastCGIfcgi2.0.0 – 2.4.4—No fix listedCNA
  • fcgi VendorFastCGI Affected 2.0.0 – 2.4.4 Fixed in — No fix listed CNA

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-23016
  2. 2026-10-03 Alias added: GHSA-9825-56cx-cfg6

References

Other 3

  • TI-2025-27301 Heap-based buffer overflow in ether FCGI CVSS 3.1MEDIUM 5.3
  • TI-2012-05391 FastCGI (aka fcgi and libfcgi) 2.4.0 allows remote attackers to cause a denial of service… CVSS 2.0MEDIUM 5.0

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences