CVE-2026-40871
7.2 · HIGHOverview
CVE-2026-40871 is a high-severity vulnerability. It was published on April 21, 2026 and has a CVSS 3.1 base score of 7.2 (HIGH).
This vulnerability has a CVSS 3.1 base score of 7.2, rated HIGH. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
Technical Description
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.
Remediation
Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Frequently Asked Questions
What is CVE-2026-40871?
CVE-2026-40871 is a high-severity vulnerability. It was published on April 21, 2026 and has a CVSS 3.1 base score of 7.2 (HIGH).
How severe is CVE-2026-40871?
This vulnerability has a CVSS 3.1 base score of 7.2, rated HIGH. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
How do I fix or remediate CVE-2026-40871?
Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-40871?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-40871 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
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