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CVE-2026-57077 CPAN Security Group
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CVE ID: CVE-2026-57077
Distribution: YAML-Syck
Versions: before 1.47
MetaCPAN: https://metacpan.org/dist/YAML-Syck
VCS Repo: https://github.com/toddr/YAML-Syck
YAML::Syck versions before 1.47 for Perl allow an out-of-bounds read
via an unbounded newline scan in newline_len
Description
-----------
YAML::Syck versions before 1.47 for Perl allow an out-of-bounds read
via an unbounded newline scan in newline_len.
In the bundled libsyck newline_len and is_newline dereference the scan
pointer, and the following byte for a "\r\n" pair, with no
NUL-terminator or bounds check. During block-scalar lexing at a
document boundary the scan runs one byte past the heap lexer buffer.
This is an incomplete fix of CVE-2025-11683, on a lexer path the
earlier fix did not cover.
Any caller that runs Load or LoadFile on an untrusted document with a
block scalar at a document boundary reaches the over-read.
Problem types
-------------
- CWE-125 Out-of-bounds Read
Solutions
---------
Upgrade to YAML-Syck 1.47 or later.
References
----------
https://metacpan.org/release/TODDR/YAML-Syck-1.47/changes
https://github.com/toddr/YAML-Syck/commit/44c90a109ec3215ee7ce747bd11209835e123d8b.patch
https://www.cve.org/CVERecord?id=CVE-2025-11683
--
Paul Johnson - [email protected]
