CVE-2026-8829

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/libwww-perl/HTML-Parser/commit/6922552b0778c90a9587a3894e248be4d3a25e1c.patch	Patch
https://github.com/libwww-perl/HTML-Parser/pull/56	Issue Tracking Patch
http://www.openwall.com/lists/oss-security/2026/06/04/2	Mailing List Third Party Advisory
https://lists.debian.org/debian-lts-announce/2026/06/msg00044.html

Configurations

Configuration 1 (hide)

cpe:2.3:a:oalders:html\:\:entities:*:*:*:*:*:perl:*:*

History

No history.

Information

Published : 2026-06-04 03:16

Updated : 2026-07-22 20:10

NVD link : CVE-2026-8829

Mitre link : CVE-2026-8829

CVE.ORG link : CVE-2026-8829

JSON object : View

Products Affected

oalders

html\

CWE

CWE-416

Use After Free

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