What’s Vulnerable › Vulnerabilities

CVE-2021-40110: Apache James IMAP vulnerable to a ReDoS

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 2.9% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2022-01-04 · updated 2026-06-17

Description

In Apache James, using Jazzer fuzzer, we identified that an IMAP user can craft IMAP LIST commands to orchestrate a Denial Of Service using a vulnerable Regular expression. This affected Apache James prior to 3.6.1 We recommend upgrading to Apache James 3.6.1 or higher , which enforce the use of RE2J regular expression engine to execute regex in linear time without back-tracking.

Affected products

• Apache Software Foundation Apache James: before 3.6.1 — fixed in 3.6.1

How to fix

Upgrade to a fixed version: Apache Software Foundation Apache James 3.6.1. Check the vendor advisory for mitigations.

References

• http://www.openwall.com/lists/oss-security/2022/01/04/2
• https://www.openwall.com/lists/oss-security/2022/01/04/2
• http://www.openwall.com/lists/oss-security/2022/01/04/2
• https://www.openwall.com/lists/oss-security/2022/01/04/2

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