postalserver postal up to 2.x SMTP Service escape output

Summaryinfo

A vulnerability was found in postalserver postal up to 2.x. It has been classified as problematic. Impacted is an unknown function of the component SMTP Service. The manipulation leads to escape output. This vulnerability is referenced as CVE-2024-27938. Remote exploitation of the attack is possible. No exploit is available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in postalserver postal up to 2.x and classified as problematic. This issue affects an unknown code block of the component SMTP Service. The manipulation with an unknown input leads to a escape output vulnerability. Using CWE to declare the problem leads to CWE-116. The product prepares a structured message for communication with another component, but encoding or escaping of the data is either missing or done incorrectly. As a result, the intended structure of the message is not preserved. Impacted is integrity. The summary by CVE is:

Postal is an open source SMTP server. Postal versions less than 3.0.0 are vulnerable to SMTP Smuggling attacks which may allow incoming e-mails to be spoofed. This, in conjunction with a cooperative outgoing SMTP service, would allow for an incoming e-mail to be received by Postal addressed from a server that a user has 'authorised' to send mail on their behalf but were not the genuine author of the e-mail. Postal is not affected for sending outgoing e-mails as email is re-encoded with `` line endings when transmitted over SMTP. This issue has been addressed and users should upgrade to Postal v3.0.0 or higher. Once upgraded, Postal will only accept End of DATA sequences which are explicitly `.`. If a non-compliant sequence is detected it will be logged to the SMTP server log. There are no workarounds for this issue.

The weakness was published 03/12/2024 as GHSA-j42r-6c99-hqf2. It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2024-27938 since 02/28/2024. The technical details are unknown and an exploit is not publicly available.

Upgrading to version 3.0.0 eliminates this vulnerability. Applying a patch is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

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Productinfo

Vendor

• postalserver

Name

• postal

Version

• 2.x

License

• open-source

Website

• Product: https://github.com/postalserver/postal/

CPE 2.3info

• 🔍

CPE 2.2info

• 🔍

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