CVE-2026-115190: Insecure Deserialization (CVSS 8)

Description

An insecure deserialization (PHP object injection) vulnerability exists in Mautic's handling of segment filters and custom field properties. Several code paths that read these stored values from the database deserialize them without restricting which PHP classes may be instantiated, instead of using Mautic's safe deserialization helper. An attacker who is able to store a crafted serialized value in these segment filter or custom field properties can cause arbitrary PHP objects to be instantiated when Mautic later processes the data, for example during segment evaluation, contact export, or custom field API requests. Combined with gadget chains available in Mautic's dependencies, this could allow an attacker to execute arbitrary code on the server, read, modify, or delete data stored in the Mautic instance, including contact data, and affect its availability. Exploitation requires high privileges or an existing ability to write to the affected stored data.

Is your site exposed to CVE-2026-115190?

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

CVSS v3.1 Score

8.0

HIGH

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

EPSS — Exploit Prediction

0.0049

Probability of exploitation

0.43%

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/mautic/mautic/security/advisories/GHSA-5r63-8h35-j3mw

Frequently Asked Questions

What is CVE-2026-115190? +

An insecure deserialization (PHP object injection) vulnerability exists in Mautic's handling of segment filters and custom field properties. Several code paths that read these stored values from the database deserialize them without restricting which PHP classes may be instantiated, instead of using Mautic's safe deserialization helper. An attacker who is able to store a crafted serialized value in these segment filter or custom field properties can cause arbitrary PHP objects to be instantiated when Mautic later processes the data, for example during segment evaluation, contact export, or custom field API requests. Combined with gadget chains available in Mautic's dependencies, this could allow an attacker to execute arbitrary code on the server, read, modify, or delete data stored in the Mautic instance, including contact data, and affect its availability. Exploitation requires high privileges or an existing ability to write to the affected stored data. It has a CVSS v3.1 base score of 8.0 (HIGH).

How severe is CVE-2026-115190? +

CVE-2026-115190 has a CVSS v3.1 score of 8.0 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0049, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-115190? +

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 …