Description
YAML::Syck versions before 1.36 for Perl has missing null-terminators which causes out-of-bounds read and potential information disclosure Missing null terminators in token.c leads to but-of-bounds read which allows adjacent variable to be read The issue is seen with complex YAML files with a hash of all keys and empty values. There is no indication that the issue leads to accessing memory outside that allocated to the module.
Affected products
toddr: yaml\
References2
- github.com/cpan-authors/YAML-Syck/pull/65 Issue Tracking
- metacpan.org/dist/YAML-Syck/changes ProductRelease Notes
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: CNA
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - EPSS — exploit probability
- 0% percentile: 24 · as of 9 November 2026
- CWE
- CWE-119
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