Threats Tagged 'cve-2026-57077'

This security update for perl-YAML-Syck addresses multiple memory-safety vulnerabilities in the libsyck library that are exploitable via the default YAML::Syck::Load() function when processing untrusted input. The fixed issues include out-of-bounds reads and use-after-free conditions that could lead to crashes or potentially other impacts. The update also hardens base64 decoding and enforces maximum depth limits to prevent stack exhaustion from deeply nested inputs.

YAML::Syck versions prior to 1.47 for Perl contain a use-after-free and double-free vulnerability triggered by redefinition or removal of anchor nodes during YAML parsing. This flaw causes the interpreter to crash, resulting in a denial of service when processing untrusted documents that redefine anchors mid-parse.

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.