CVE-2026-13401: XML::Bare versions through 0.53 for Perl will hang in an infinite loop when parsing malformed attributes

[Robert Rothenberg <rrwo () cpansec org>]

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CVE-2026-13401                                       CPAN Security Group
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        CVE ID:  CVE-2026-13401
  Distribution:  XML-Bare
      Versions:  through 0.53

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


XML::Bare versions through 0.53 for Perl will hang in an infinite loop
when parsing malformed attributes

Description
-----------
XML::Bare versions through 0.53 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.

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

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


References
----------
https://github.com/nanoscopic/perl-XML-Bare/pull/2
https://security.metacpan.org/patches/X/XML-Bare/0.53/CVE-2026-13401-r1.patch