What’s Vulnerable › Vulnerabilities

CVE-2023-51747: SMTP smuggling in Apache James

• Severity: high (CVSS 7.1 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.0% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2024-02-27 · updated 2026-06-17
• Weakness: CWE-20

Description

Apache James prior to versions 3.8.1 and 3.7.5 is vulnerable to SMTP smuggling. A lenient behaviour in line delimiter handling might create a difference of interpretation between the sender and the receiver which can be exploited by an attacker to forge an SMTP envelop, allowing for instance to bypass SPF checks. The patch implies enforcement of CRLF as a line delimiter as part of the DATA transaction. We recommend James users to upgrade to non vulnerable versions.

Affected products

• Apache Software Foundation Apache James: 3.7.5, 3.8.1

References

• http://www.openwall.com/lists/oss-security/2024/02/27/4
• https://lists.apache.org/thread/rxkwbkh9vgbl9rzx1fkllyk3krhgydko
• https://postfix.org/smtp-smuggling.html
• https://sec-consult.com/blog/detail/smtp-smuggling-spoofing-e-mails-worldwide/
• http://www.openwall.com/lists/oss-security/2024/02/27/4
• https://lists.apache.org/thread/rxkwbkh9vgbl9rzx1fkllyk3krhgydko
• https://postfix.org/smtp-smuggling.html
• https://sec-consult.com/blog/detail/smtp-smuggling-spoofing-e-mails-worldwide/

Get alerted when CVE-2023-51747 or the next vulnerability affects your stack