======================================================================== CVE-2026-57075 CPAN Security Group ========================================================================

CVE ID: CVE-2026-57075 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 a signed-char lookup-table index in syckbase64dec

Description ----------- YAML::Syck versions before 1.47 for Perl allow an out-of-bounds read via a signed-char lookup-table index in syckbase64dec.

The base64 decoder in the bundled libsyck indexes the 256-entry static table b64xtable with a signed char, so any !!binary byte >= 0x80 sign-extends to a negative index and reads before the table. The decoder receives the raw bytes of any !!binary node, a standard YAML type not gated by $LoadBlessed or $LoadCode, so it is reached on the default Load path.

Any caller that runs Load or LoadFile on an untrusted document containing a !!binary scalar with a high-bit byte triggers the read, and the value read can surface in the decoded result.

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

-- Paul Johnson - paul () pjcj net