CPANSA-YAML-2017-20285: YAML vulnerability

Publisher giterlizzi Document category csaf_security_advisory
Initial release date 2026-10-05T00:00:00 Engine CSAF Perl Toolkit 0.26
Current release date 2026-10-05T00:00:00 Build Date
Current version 1 Status final
CVSS v3.1 Base Score 9.1 Severity Critical
Original language Language en
Also referred to

Vulnerability Description

YAML versions before 1.30 for Perl allow a loaded document to trigger the DESTROY method of arbitrary classes.

A perl/hash:Class tag blesses a hash into the class it names. The document supplies the object's fields, and Perl calls DESTROY when it goes out of scope.

What DESTROY does depends on the classes the process has loaded. With File::Temp::Dir from core Perl, it can delete a directory tree the document names.

Vulnerabilities

CVE-2017-20285

Vulnerability Description

YAML versions before 1.30 for Perl allow a loaded document to trigger the DESTROY method of arbitrary classes.

A perl/hash:Class tag blesses a hash into the class it names. The document supplies the object's fields, and Perl calls DESTROY when it goes out of scope.

What DESTROY does depends on the classes the process has loaded. With File::Temp::Dir from core Perl, it can delete a directory tree the document names.

Weakness CWE-470 : Use of Externally-Controlled Input to Select Classes or Code ('Unsafe Reflection')

Product status

Known affected
Product Score
YAML less than 1.30
CVSS Version CVSS Vector CVSS Base Score CVSS Base Severity
3.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N 9.1 Critical
Fixed

giterlizzi

Namespace: https://github.com/giterlizzi/

gdt@cpan.org

References

Revision history

Version Date of the revision Summary of the revision
1 Mon Oct 5 00:00:00 2026 First release

Sharing rules

TLP:WHITE
For the TLP version see: https://www.first.org/tlp/