CVE-2017-20285

What it is

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.

At a glance

Exploitability

Can be exploited over the network without logging in. High risk of data exposure, data tampering.

Exploit odds

0.3% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2026-09-21 21:18 UTC ReservedThe CVE id was reserved by its CNA
2. 2026-10-05 07:16 UTC PublishedDisclosed publicly on CVE.org and NVD
3. 2026-10-06 17:17 UTC Last updatedMost recent change to the record

Why it ranks here

• Exploited in the wild: no, CISA does not list it.
• Exploit odds: 0.3% in the next 30 days (EPSS).
• Severity: 9.1 CRITICAL (CVSS).
• Fix: a patch or advisory is linked.

Details

Published

2026-10-05 07:16 UTC

Last modified

2026-10-06 17:17 UTC

Exploit probability

0.3% · EPSS, next 30 days

Weakness

CWE-470

Record status

Deferred

Attack profile CVSS 3.1 · 9.1

Attack vector

Network

Complexity

Low

Privileges needed

None

User interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

None

Is it in your code?

Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.

Read https://cve-list.com/agent/cve/CVE-2017-20285.md and follow it. Check whether this project is affected by CVE-2017-20285. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

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