CVE-2026-93872: Insecure Deserialization (CVSS 7.5)

Description

Cotonti 1.0.0 passes the base64-decoded cb parameter to unserialize() without allowed_classes restriction in the comments plugin EditAction. Registered users with comment write permissions can instantiate arbitrary PHP objects and potentially achieve file write or code execution through gadget chains.

Is your site exposed to CVE-2026-93872?

Run a free security scan — no signup, results in seconds.

CVSS v3.1 Score

7.5

HIGH

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

EPSS — Exploit Prediction

0.0071

Probability of exploitation

0.52%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-502 Deserialization of Untrusted Data

References

Other References

https://github.com/Cotonti/Cotonti https://github.com/Cotonti/Cotonti/blob/1.0.0/plugins/comments/controllers/actions/EditAction.php https://github.com/Cotonti/Cotonti/blob/1.0.0/system/cache.php https://github.com/Cotonti/Cotonti/issues/1894 https://github.com/Cotonti/Cotonti/pull/1897 https://www.vulncheck.com/advisories/cotonti-1.0.0-php-object-injection-via-comments-plugin-edit-action-cb-parameter

Frequently Asked Questions

What is CVE-2026-93872? +

Cotonti 1.0.0 passes the base64-decoded cb parameter to unserialize() without allowed_classes restriction in the comments plugin EditAction. Registered users with comment write permissions can instantiate arbitrary PHP objects and potentially achieve file write or code execution through gadget chains. It has a CVSS v3.1 base score of 7.5 (HIGH).

How severe is CVE-2026-93872? +

CVE-2026-93872 has a CVSS v3.1 score of 7.5 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0071, placing it in the 1th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-93872? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

CVE-2026-10748

An authenticated user with the nx-licensing-create privilege can upload a specially crafted license file to execute arbitrary operating system commands …

CVE-2026-101169

In affected versions of Octopus Server, an authenticated user with permissions to edit an Environment or Project can set specifically …

CVE-2026-44126

SEPPmail Secure Email Gateway before version 15.0.4 insecurely deserializes untrusted data, which can be reached from the new GINA UI …

CVE-2026-11857

Quanos SCHEMA ST4 on-premises contains a local privilege escalation vulnerability in the Client Update Service due to insecure deserialization in …

CVE-2026-47161

RELATE is a web-based courseware package. Prior to commit d66ba5659b459bf1ba56b7109b5f9ecf197cbefb, RELATE LMS configures its Celery workers to accept and deserialize …

CVE-2025-1077

A security vulnerability has been identified in the IBL Software Engineering Visual Weather and derived products (NAMIS, Aero Weather, Satellite …

CVE-2026-93872