Security Digest · Vulnerability record
CVE-2020-35125: Mautic is vulnerable to XSS vulnerability
A cross-site scripting (XSS) vulnerability in the forms component of Mautic before 3.2.4 allows remote attackers to inject executable JavaScript via mautic[return] (a different attack method than CVE-2020-35124, but also related to the Referer concept).
CVSS 9.6 Critical EPSS 2.7% · p86
Should you act?
Critical and remotely reachable
No known exploitation yet, but it is network-reachable without credentials. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.
- No confirmed exploitation. It is not in CISA’s KEV catalog. That can change quickly after a public write-up; re-check if you are affected.
- EPSS 2.7%, percentile 86: FIRST’s model estimates a 2.7% chance of exploitation activity in the next 30 days, higher than 86% of all scored CVEs (elevated). EPSS is a probability, not a verdict.
- Needs a user to click or open something. Phishing makes that realistic, but it is not wormable.
- Only applies if your dependency tree includes
mautic/core(Composer (PHP)) < 2.16.5, fixed in 2.16.5;mautic/core(Composer (PHP)) >= 3.0.0, < 3.2.4, fixed in 3.2.4. Check your lockfile, including transitive dependencies.
What it is
A cross-site scripting (XSS) vulnerability in the forms component of Mautic before 3.2.4 allows remote attackers to inject executable JavaScript via mautic[return] (a different attack method than CVE-2020-35124, but also related to the Referer concept).
From the GitHub advisory
Impact This is a cross-site scripting vulnerability which affects every version of Mautic and could allow an attacker unauthorised administrator level access to Mautic.
This vulnerability was reported by Naveen Sunkavally at Horizon3.ai.
Patches Upgrade to 3.2.4 or 2.16.5.
Link to patch for 2.x versions: https://github.com/mautic/mautic/compare/2.16.4...2.16.5.diff
Link to patch for 3.x versions: https://github.com/mautic/mautic/compare/3.2.2...3.2.4.diff
Weakness type: CWE-79.
Product: mautic/core (Composer (PHP)) · Assigned by: mitre · Published: 2021-02-09
Affected and fixed versions
| Ecosystem | Package | Vulnerable | First fixed |
|---|---|---|---|
| Composer (PHP) | mautic/core | < 2.16.5 | 2.16.5 |
| Composer (PHP) | mautic/core | >= 3.0.0, < 3.2.4 | 3.2.4 |
| Vendor | Product | Affected versions (per CVE record) |
|---|---|---|
| n/a | n/a | see vendor advisory |
Severity scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub | 3.1 | 9.6 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H |
- Attack vector: network (remotely reachable)
- Attack complexity: low
- Privileges required: none (no login)
- User interaction: required (a user must click/open something)
- Scope: changed (can affect other components)
CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.
Exploitation and urgency
- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- FIRST EPSS (model of 2026-10-21): 2.69% probability of exploitation activity in the next 30 days; percentile 86.
Timeline
- — CVE record published by mitre
- — GitHub-reviewed advisory GHSA-42q7-95j7-w62m published (critical)
- — CVE record last updated
Sources and references
Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.
Vulnerability records
- GitHub Advisory GHSA-42q7-95j7-w62m github.com
- CVE.org record CVE-2020-35125 cve.org
- NVD entry CVE-2020-35125 nvd.nist.gov
Other references from the CVE record and advisory
- forum.mautic.org forum.mautic.org
- mautic.org mautic.org
- horizon3.ai horizon3.ai
- github.com github.com
- github.com github.com
- packagist.org packagist.org
Critical Composer (PHP) advisories · Today’s Security Digest