CVE-2008-5557

Severity: critical (CVSS 10.0 v2.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 7.4% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2008-12-23 · updated 2026-06-16
Weakness: CWE-119

Description

Heap-based buffer overflow in ext/mbstring/libmbfl/filters/mbfilter_htmlent.c in the mbstring extension in PHP 4.3.0 through 5.2.6 allows context-dependent attackers to execute arbitrary code via a crafted string containing an HTML entity, which is not properly handled during Unicode conversion, related to the (1) mb_convert_encoding, (2) mb_check_encoding, (3) mb_convert_variables, and (4) mb_parse_str functions.

Affected products

PHP: 4.3.0, 4.3.1, 4.3.2, 4.3.3, 4.3.4, 4.3.5 (+43)

References

http://archives.neohapsis.com/archives/fulldisclosure/2008-12/0477.html
http://bugs.php.net/bug.php?id=45722
http://cvs.php.net/viewvc.cgi/php-src/ext/mbstring/libmbfl/filters/mbfilter_htmlent.c?r1=1.7&r2=1.8
http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?objectID=c02029444
http://lists.apple.com/archives/security-announce/2009/May/msg00002.html
http://lists.opensuse.org/opensuse-security-announce/2009-02/msg00002.html
http://lists.opensuse.org/opensuse-security-announce/2009-04/msg00003.html
http://marc.info/?l=bugtraq&m=124654546101607&w=2
http://marc.info/?l=bugtraq&m=125631037611762&w=2
http://secunia.com/advisories/34642
http://secunia.com/advisories/35003
http://secunia.com/advisories/35074

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