CVE-2026-6104

Publication date 11 May 2026

Last updated 13 May 2026


Ubuntu priority

Description

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.

Read the notes from the security team

Status

Package Ubuntu Release Status
php5 26.04 LTS resolute Not in release
25.10 questing Not in release
24.04 LTS noble Not in release
22.04 LTS jammy Not in release
14.04 LTS trusty
Needs evaluation
php7.0 26.04 LTS resolute Not in release
25.10 questing Not in release
24.04 LTS noble Not in release
22.04 LTS jammy Not in release
16.04 LTS xenial
Needs evaluation
php7.2 26.04 LTS resolute Not in release
25.10 questing Not in release
24.04 LTS noble Not in release
22.04 LTS jammy Not in release
18.04 LTS bionic
Needs evaluation
php7.4 26.04 LTS resolute Not in release
25.10 questing Not in release
24.04 LTS noble Not in release
22.04 LTS jammy Not in release
20.04 LTS focal
Needs evaluation
php8.1 26.04 LTS resolute Not in release
25.10 questing Not in release
24.04 LTS noble Not in release
22.04 LTS jammy
Needs evaluation
php8.3 26.04 LTS resolute Not in release
25.10 questing Not in release
24.04 LTS noble
Needs evaluation
22.04 LTS jammy Not in release
php8.4 26.04 LTS resolute Not in release
25.10 questing
Needs evaluation
24.04 LTS noble Not in release
22.04 LTS jammy Not in release

Notes


sbeattie

PEAR issues should go against php-pear as of xenial


Access our resources on patching vulnerabilities