CVE-2024-31204Public exploitNetwork attack vector

Administrator session hijacking via unescaped exception details

Published Apr 4, 2024 · Updated Dec 12, 2024

Stored XSS in mailcow: dockerized before 2024-04 allows remote attackers to execute scripts in an administrator's browser. The exception handler uses print_r() to place attacker-controlled json_api.php query arguments in session alerts, and footer.inc.php passes them to an HTML-rendering notification library without entity encoding. Exploitation requires an administrator to open a crafted email while signed in and then revisit the admin panel, enabling session hijacking and unauthorized administrative actions.

CVSS severity6.8
Medium
EPSS probability8.25%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Stored XSS in mailcow: dockerized before 2024-04 allows remote attackers to execute scripts in an administrator's browser. The exception handler uses print_r() to place attacker-controlled json_api.php query arguments in session alerts, and footer.inc.php passes them to an HTML-rendering notification library without entity encoding. Exploitation requires an administrator to open a crafted email while signed in and then revisit the admin panel, enabling session hijacking and unauthorized administrative actions.

The record

CVE
CVE-2024-31204
Published
Apr 4, 2024
Updated
Dec 12, 2024
Vendor
mailcow
Product
mailcow: dockerized
Classifications
CWE-79, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 4, 2024CVE publishedPublication date reported by the CVE source.
  2. Dec 12, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <2024-04
  2. Affected versionversion=< 2024-04

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

mailcow · mailcow: dockerizedversion=0 <2024-04; version=< 2024-04

Published CVSS scores

6.8GitHub, Inc.CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1190Exploit Public-Facing Application

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo