USN-6939-1: Exim vulnerability

31 July 2024

Exim could be made to bypass a MIME filename extension-blocking protection mechanism if it received specially crafted input.

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Releases

Packages

  • exim4 - Exim is a mail transport agent

Details

Phillip Szelat discovered that Exim misparses multiline MIME header
filenames. A remote attacker could use this issue to bypass a MIME filename
extension-blocking protection mechanism and possibly deliver executable
attachments to the mailboxes of end users.

Reduce your security exposure

Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines.

Learn more about Ubuntu Pro

Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 24.04
Ubuntu 22.04
Ubuntu 20.04
Ubuntu 18.04
Ubuntu 16.04

In general, a standard system update will make all the necessary changes.

References

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Further reading