OALDERS HTML::Entities up to 3.83 on Perl grow_gap SV use after free

Summaryinfo

A vulnerability classified as critical was found in OALDERS HTML::Entities up to 3.83 on Perl. The affected element is the function grow_gap. Executing a manipulation of the argument SV can lead to use after free. This vulnerability is tracked as CVE-2026-8829. The attack can be launched remotely. No exploit exists. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in OALDERS HTML::Entities up to 3.83 on Perl. It has been declared as critical. This vulnerability affects the function grow_gap. The manipulation of the argument SV with an unknown input leads to a use after free vulnerability. The CWE definition for the vulnerability is CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

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.

The advisory is available at github.com. This vulnerability was named CVE-2026-8829 since 05/18/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. Technical details are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 318663 (Linux Distros Unpatched Vulnerability : CVE-2026-8829), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 3.84 eliminates this vulnerability. Applying the patch 6922552b0778c90a9587a3894e248be4d3a25e1c is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (318663) and EUVD (EUVD-2026-34194). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Vendor

• OALDERS

Name

• HTML::Entities

Version

• 3.0
• 3.1
• 3.2
• 3.3
• 3.4
• 3.5
• 3.6
• 3.7
• 3.8
• 3.9
• 3.10
• 3.11
• 3.12
• 3.13
• 3.14
• 3.15
• 3.16
• 3.17
• 3.18
• 3.19
• 3.20
• 3.21
• 3.22
• 3.23
• 3.24
• 3.25
• 3.26
• 3.27
• 3.28
• 3.29
• 3.30
• 3.31
• 3.32
• 3.33
• 3.34
• 3.35
• 3.36
• 3.37
• 3.38
• 3.39
• 3.40
• 3.41
• 3.42
• 3.43
• 3.44
• 3.45
• 3.46
• 3.47
• 3.48
• 3.49
• 3.50
• 3.51
• 3.52
• 3.53
• 3.54
• 3.55
• 3.56
• 3.57
• 3.58
• 3.59
• 3.60
• 3.61
• 3.62
• 3.63
• 3.64
• 3.65
• 3.66
• 3.67
• 3.68
• 3.69
• 3.70
• 3.71
• 3.72
• 3.73
• 3.74
• 3.75
• 3.76
• 3.77
• 3.78
• 3.79
• 3.80
• 3.81
• 3.82
• 3.83

License

• open-source

CPE 2.3info

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CPE 2.2info

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Sourcesinfo

Entryinfo

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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