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CVE-2008-5557

HIGH severity · CVSS 10 · Memory corruption
10CVSS HIGH

Summary

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.

Impact & exploitability

Attack vectorNetwork
Attack complexityLow
Privileges required
User interaction
Confidentiality impact
Integrity impact
Availability impact
Exploit probability (EPSS)30%

AV:N/AC:L/Au:N/C:C/I:C/A:C

Affected products we track (1)

PHP

Recommendation

Apply the vendor fix promptly. Open any affected product above for its exact safe version.

Last checked: Wed, 10 Jun 2026 22:18:30 UTC