CVE-2026-13397: HTML::Bare versions through 0.04 for Perl will hang in an infinite loop when parsing malformed attributes

[Robert Rothenberg <rrwo () cpansec org>]

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CVE-2026-13397                                       CPAN Security Group
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        CVE ID:  CVE-2026-13397
  Distribution:  HTML-Bare
      Versions:  through 0.04

      MetaCPAN:  https://metacpan.org/dist/HTML-Bare
      VCS Repo:  https://github.com/nanoscopic/perl-HTML-Bare


HTML::Bare versions through 0.04 for Perl will hang in an infinite loop
when parsing malformed attributes

Description
-----------
HTML::Bare versions through 0.04 for Perl will hang in an infinite loop
when parsing malformed attributes.

The parserc_parse function never advances the attribute-parse state
cursor on certain malformed attribute forms, looping forever.

Nameless attributes such as "<a ='c'>" or unbalanced quotes "<a
b='''''''c'>" can trigger this condition.

Note that the latest version available on CPAN is version 0.02. Newer
versions are available on the git repository.

Problem types
-------------
- CWE-835 Loop with Unreachable Exit Condition ('Infinite Loop')

Workarounds
-----------
Apply the patch.


References
----------
https://github.com/nanoscopic/perl-HTML-Bare/pull/1
https://security.metacpan.org/patches/H/HTML-Bare/0.02/CVE-2026-13397-r1.patch