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.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| OALDERS | HTML::Entities | < 3.84 | 3.84 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | libhtml-parser-perl | 3.83-2 | — |
| Debian 13 | libhtml-parser-perl | 3.83-2~deb13u1 | — |
| Debian 12 | libhtml-parser-perl | 3.81-1+deb12u1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.04 LTS | libhtml-parser-perl | 3.83-1ubuntu0.1 | USN-8587-1 |
| Ubuntu 25.10 | libhtml-parser-perl | No fix yet | — |
| Ubuntu 24.04 LTS | libhtml-parser-perl | 3.81-1ubuntu0.1 | USN-8587-1 |
| Ubuntu 22.04 LTS | libhtml-parser-perl | 3.76-1ubuntu0.1 | USN-8587-1 |
| Ubuntu 20.04 LTS | libhtml-parser-perl | No fix yet | — |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 18.04 LTS | libhtml-parser-perl | No fix yet | — |
| Ubuntu 16.04 LTS | libhtml-parser-perl | No fix yet | — |
| Ubuntu 14.04 LTS | libhtml-parser-perl | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | perl-HTML-Parser | 3.830.0-150000.3.6.1 | SUSE-SU-2026:2950-1 |
| SLES 12 SP5 | perl-HTML-Parser | 3.71-3.3.1 | SUSE-SU-2026:2948-1 |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | perl-HTML-Parser | 3.830.0-160000.3.1 | SUSE-SU-2026:22189-1 |
| SLES 16.0 | perl-HTML-Parser | 3.830.0-160000.3.1 | SUSE-SU-2026:22189-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | perl-HTML-Parser | 3.850.0-1.1 | openSUSE-SU-2026:10957-1 |
| openSUSE Leap 16.0 | perl-HTML-Parser | 3.830.0-160000.3.1 | openSUSE-SU-2026:21126-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | perl-HTML-Parser +1 | 3.76-1.amzn2023.0.4 | ALAS2023-2026-1836 |
| Amazon Linux 2 | perl-HTML-Parser | 3.71-4.amzn2.0.3 | ALAS2-2026-3357 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | perl-HTML-Parser | 3.82-2 | — |
Advisories 10
- WID-SEC-2026-2858 IBM AIX und VIOS: Mehrere Schwachstellen BSI CERT-Bund (WID) · Oct 4, 2026
- NCSC-2026-0321 Meerdere kwetsbaarheden verholpen in IBM AIX en IBM PowerVM VIOS NCSC-NL (Netherlands) · Aug 21, 2026
- USN-8587-1 libhtml-parser-perl vulnerability Ubuntu Security Notices (USN) · Jul 22, 2026
- SUSE-SU-2026:2950-1 Security update for perl-HTML-Parser SUSE / openSUSE Security Updates · Jul 15, 2026
- SUSE-SU-2026:2948-1 Security update for perl-HTML-Parser SUSE / openSUSE Security Updates · Jul 15, 2026
- openSUSE-SU-2026:21126-1 Security update for perl-HTML-Parser SUSE / openSUSE Security Updates · Jun 30, 2026
- SUSE-SU-2026:22189-1 Security update for perl-HTML-Parser SUSE / openSUSE Security Updates · Jun 24, 2026
- ALAS2-2026-3357 Low: perl-HTML-Parser security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · Jun 22, 2026
- ALAS2023-2026-1836 Low: perl-HTML-Parser security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Jun 22, 2026
- openSUSE-SU-2026:10957-1 perl-HTML-Parser-3.850.0-1.1 on GA media SUSE / openSUSE Security Updates · Jun 5, 2026