Heap Memory Vulnerability in HTML::Entities for Perl by libwww-perl
CVE-2026-8829

7.5HIGH

Key Information:

Vendor

Oalders

Status
Html::entities
Vendor
CVE Published:
4 June 2026

What is CVE-2026-8829?

A vulnerability in HTML::Entities versions prior to 3.84 for Perl can lead to the reading of freed heap memory. This occurs due to improper handling of pointers within the XS routine backing HTML::Entities::_decode_entities. When an input scalar value is identical to a value scalar in the entity2char hash and that value references its own key, it can cause the backing allocation to be freed during a buffer reallocation. Subsequent operations may inadvertently read from this freed memory, potentially exposing adjacent heap contents. This situation creates a risk of sensitive data leakage and requires prompt remediation.

Affected Version(s)

HTML::Entities 0 < 3.84

References

https://github.com/libwww-perl/HTML-Parser/pull/56
patch
https://github.com/libwww-perl/HTML-Parser/commit/6922552...
patch

CVSS V3.1

Score:
7.5
Severity:
HIGH
Confidentiality:
High
Integrity:
None
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.