CVE-2026-57075 (GCVE-0-2026-57075)

Vulnerability from cvelistv5 – Published: 2026-07-16 21:39 – Updated: 2026-07-17 13:08
VLAI
Title
YAML::Syck versions before 1.47 for Perl allow an out-of-bounds read via a signed-char lookup-table index in syck_base64dec
Summary
YAML::Syck versions before 1.47 for Perl allow an out-of-bounds read via a signed-char lookup-table index in syck_base64dec. The base64 decoder in the bundled libsyck indexes the 256-entry static table b64_xtable 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.
Severity
9.1 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-17 13:08 UTC
CWE
Assigner
CPANSec CNA under the redhat root
CNA scorecard C 64/100 over 265 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
TODDR YAML::Syck Affected: 0 , < 1.47 (custom)
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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