CVE-2021-36564

Name: CVE-2021-36564
Creator: NVD / NIST
Published: 2021-12-06T21:15:07.71+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.8/10EPSS 1.84%

Last modified Jun 17, 2026

CVE-2021-36564 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. ThinkPHP v6.0.8 was discovered to contain a deserialization vulnerability via the component vendor\league\flysystem-cached-adapter\src\Storage\Adapter.php.. EPSS estimates a 1.84% chance of exploitation in the next 30 days.

Description

ThinkPHP v6.0.8 was discovered to contain a deserialization vulnerability via the component vendor\league\flysystem-cached-adapter\src\Storage\Adapter.php.

Metrics

CVSS 3.1

9.8/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS Probability

1.84%

76.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-502

Affected Software

Vendor	Product	Versions
Thinkphp	Thinkphp	6.0.8

References

https://github.com/top-think/framework/issues/2559Exploit, Third Party Advisory
https://github.com/top-think/framework/issues/2559Exploit, Third Party Advisory

Timeline

Published: Dec 6, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-36564?

ThinkPHP v6.0.8 was discovered to contain a deserialization vulnerability via the component vendor\league\flysystem-cached-adapter\src\Storage\Adapter.php.

How severe is CVE-2021-36564?

CVE-2021-36564 has a CVSS score of 9.8/10 (CRITICAL severity). The EPSS model estimates a 1.84% probability of exploitation in the next 30 days.

How do I fix CVE-2021-36564?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-36564?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST