CVE-2026-57077

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.

CVSS v3 7.7 HIGH

7.7^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.5 / Impact : 5.2

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/toddr/YAML-Syck/commit/44c90a109ec3215ee7ce747bd11209835e123d8b.patch
https://metacpan.org/release/TODDR/YAML-Syck-1.47/changes
https://www.cve.org/CVERecord?id=CVE-2025-11683

Configurations

No configuration.

History

No history.

Information

Published : 2026-07-16 22:17

Updated : 2026-07-17 15:07

NVD link : CVE-2026-57077

Mitre link : CVE-2026-57077

CVE.ORG link : CVE-2026-57077

JSON object : View

Products Affected

No product.

CWE

CWE-125

Out-of-bounds Read

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