YAML::Syck versions before 1.36 for Perl has missing null-terminators which causes out-of-bounds read and potential information disclosure
Missing null terminators in token.c leads to but-of-bounds read which allows adjacent variable to be read
The issue is seen with complex YAML files with a hash of all keys and empty values. There is no indication that the issue leads to accessing memory outside that allocated to the module.
Exploitability
AV:AAC:LPR:NUI:NScope
S:UImpact
C:HI:NA:N6.5/CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:NMemory Safety