CVE-2026-40871

mailcow: dockerized is an open source groupware/email suite based on docker. Versions prior to 2026-03b have a second-order SQL injection vulnerability in the quarantine_category field via the Mailcow API. The /api/v1/add/mailbox endpoint stores quarantine_category without validation or sanitization. This value is later used by quarantine_notify.py, which constructs SQL queries using unsafe % string formatting instead of parameterized queries. This results in a delayed (second-order) SQL injection when the quarantine notification job executes, allowing an attacker to inject arbitrary SQL. Using a UNION SELECT, sensitive data (e.g., admin credentials) can be exfiltrated and rendered inside quarantine notification emails. Version 2026-03b fixes the vulnerability.

CVSS v3 7.2 HIGH

7.2^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.2 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required HIGH

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/mailcow/mailcow-dockerized/security/advisories/GHSA-r8fq-wrfm-cj2q
https://github.com/mailcow/mailcow-dockerized/security/advisories/GHSA-r8fq-wrfm-cj2q

Configurations

No configuration.

History

No history.

Information

Published : 2026-04-21 20:17

Updated : 2026-06-17 10:45

NVD link : CVE-2026-40871

Mitre link : CVE-2026-40871

CVE.ORG link : CVE-2026-40871

JSON object : View

Products Affected

No product.

CWE

CWE-20

Improper Input Validation

CWE-89

Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection')

CWE-116

Improper Encoding or Escaping of Output

CWE-564

SQL Injection: Hibernate

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