CVE-2017-20285

CriticalCVSS 9.1

Published: 05/10/2026(UTC)Updated: 06/10/2026(UTC)Translated: 05/10/2026(UTC)NVD NIST

Exploitation Probability (EPSS)

Low risk

0.18%

7th percentile - higher than 7% of all known CVEs

Summary

YAML before version 1.30 for Perl allows a loaded document to trigger the DESTROY method of arbitrary classes. The perl/hash:Class tag blesses a hash into the class it names, and Perl calls DESTROY when it goes out of scope.

Risk Assessment

An attacker can exploit DESTROY methods of classes like File::Temp::Dir to delete a directory tree, potentially leading to data loss or service disruption.

Recommendation

Update YAML to version 1.30 or later and do not process untrusted YAML documents.

Other vulnerabilities in YAML

CVE-2019-25777High
YAML before version 1.27_001 for Perl allows a loaded perl/glob document to replace any package variable, which can lead to arbitrary code execution. The document can enable code loading options that are off by default.

Original NVD description (English source)

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.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS