Critical 9.1

CVE-2017-20285

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.

Scores

CVSS out of 10, critical severity.

EPSS chance of exploitation in the next 30 days.

The facts

Published

5 October 2026

Last changed

6 October 2026

NVD status

Deferred

Severity

Critical, CVSS 9.1 out of 10 (version 3.1)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Weakness

Known exploited

Not in the CISA Known Exploited Vulnerabilities catalogue in this build.

EPSS

0.3% chance of exploitation activity in the next 30 days (percentile 24).

Is there a Securelyn advisory?

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Scores

The facts

Is there a Securelyn advisory?

References