HTML::Entities versions before 3.84 for Perl read freed heap memory in _decode_entities
At a glance
Severity
HIGH 7.5
EPSS
EPSS 0.41 % · percentile 35 (2026-10-27)
State
PUBLISHED
Published
Updated
Assigner
CPANSec
NVD status
Modified
Description
HTML::Entities versions before 3.84 for Perl read freed heap memory in _decode_entities.
The XS routine backing HTML::Entities::_decode_entities cached a pointer (repl) into the entity-value SV returned by hv_fetch on the entity2char hash. When the input SV was identical to a value SV in that hash, and that value contained its own key as an entity reference, a later call to grow_gap() reallocated the SV's PV buffer and freed the backing allocation that repl still pointed into. The subsequent copy loop read repl_len bytes from the freed allocation.
The read may disclose adjacent heap contents into the destination SV.
