🛡️ CVE-2021-21704 — libphp

🟡 CVSS 5.0 — Medium ✅ No Known Exploit OSV
5.0
CVSS Score
0 Low4 Medium7 High9 Critical10

Description

Multiple vulnerabilities in Firebird client extension

In PHP versions 7.3.x below 7.3.29, 7.4.x below 7.4.21 and 8.0.x below 8.0.8, when using Firebird PDO driver extension, a malicious database server could cause crashes in various database functions, such as getAttribute(), execute(), fetch() and others by returning invalid response data that is not parsed correctly by the driver. This can result in crashes, denial of service or potentially memory corruption.

Affected software

CVE-2021-21704 is recorded against 3 packages.

  • libphp
  • php
  • php-min

Timeline and source

Published on 11 August 2025. No public exploit is currently recorded for this entry. Record sourced from OSV.

References

bugs.php.net (Web)
bugs.php.net (Web)
bugs.php.net (Web)
bugs.php.net (Web)
nvd.nist.gov (Web)
security.gentoo.org (Web)
security.netapp.com (Web)

CVE-2021-21704 on other distributions

Each distribution ships its own build and its own fixed version. Pick the one you run:

Details

Severity MEDIUM
CVSS Score 5.0
CVSS Vector N/A
CWE N/A
Public Exploit ✅ No
Source OSV
Published 2025-08-11
Updated 2026-08-12
Modified 2025-08-11
Fix URL N/A

Affected Packages

Software From version Fixed in
libphp — —
php — —
php-min — —

Similar Threats

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