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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-40875 Detail

Description

mailcow: dockerized is an open source groupware/email suite based on docker. In versions prior to 2026-03b, the user dashboard's "Seen successful connections" (login history) renders the client IP from login logs without HTML escaping. Because the server trusts the X-Real-IP header as the source IP for logging, an attacker can inject HTML/JS into this field. This Self-XSS can be exploited by a Login CSRF to force the victim into the attacker's account, and then read emails in a previous browser tab. Version 2026-03b fixes the vulnerability.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

Nist CVSS score does not match with CNA score
CNA:  GitHub, Inc.
CVSS-B 7.0 HIGH
Vector:  CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:P/VC:H/VI:N/VA:N/SC:H/SI:H/SA:N

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/mailcow/mailcow-dockerized/security/advisories/GHSA-jprq-w83q-q62h CISA-ADP, GitHub, Inc.

Weakness Enumeration

CWE-ID CWE Name Source
CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') GitHub, Inc.  
CWE-80 Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS) GitHub, Inc.  

Change History

2 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-40875
NVD Published Date:
04/21/2026
NVD Last Modified:
04/22/2026
Source:
GitHub, Inc.