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🛡️ CVE-2026-6104 — libphp

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

Description

Global buffer over-read in mb_convert_encoding() with attacker-supplied encoding

In PHP versions 8.4.* before 8.4.21 and 8.5.* before 8.5.6, when an encoding name containing an embedded NUL byte is passed to mb_convert_encoding() or related mbstring functions, the code incorrectly assumes that when strncasecmp() returns 0 it means the strings have the same length. This can lead to out-of-bounds read of global memory, potentially causing a crash or information disclosure or crash. Affected functions include mb_convert_encoding(), mb_detect_encoding(), mb_convert_variables(), and mb_detect_order(), as well as the mbstring.detect_order and mbstring.http_output INI settings.

Affected software

CVE-2026-6104 is recorded against 3 packages.

  • libphp
  • php
  • php-min

Timeline and source

Published on 12 May 2026 and last revised on 6 July 2026. No public exploit is currently recorded for this entry. Record sourced from OSV.

References

github.com (Web)
nvd.nist.gov (Web)
access.redhat.com (Web)
access.redhat.com (Web)
bugzilla.redhat.com (Web)
security.access.redhat.com (Web)

Other advisories for this package

libphp has other advisories on record. If you are patching this one, these are worth checking on the same host:

CVE-2026-6104 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 2026-05-12
Updated 2026-08-20
Modified 2026-07-06
Fix URL N/A

Affected Packages

Software From version Fixed in
libphp
php
php-min

Similar Threats

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ⓘ Data Notice: The information presented above has been compiled from publicly available internet sources. Boteraser aggregates this data solely for informational purposes and does not independently classify, evaluate, or endorse any findings about the vulnerabilities listed. The accuracy and completeness of this information is the sole responsibility of the original publishers. Boteraser and its operators accept no liability for any decisions made based on this data.

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