CVE-2023-51747: james Input Validation Flaw — Fix

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.

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CVSS v3.1 Score

7.1

HIGH

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N

Weakness Type (CWE)

CWE-20 Improper Input Validation

CWE-290 CWE-290

CWE-444 CWE-444

Affected Products

Vendor	Product	Versions
apache	james	All
apache	james	All

References

Advisories & Patches

https://lists.apache.org/thread/rxkwbkh9vgbl9rzx1fkllyk3krhgydko https://lists.apache.org/thread/rxkwbkh9vgbl9rzx1fkllyk3krhgydko

Other References

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

Frequently Asked Questions

What is CVE-2023-51747? +

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. It has a CVSS v3.1 base score of 7.1 (HIGH).

How severe is CVE-2023-51747? +

CVE-2023-51747 has a CVSS v3.1 score of 7.1 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2023-51747? +

CVE-2023-51747 affects products from apache, specifically: james. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2023-51747? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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