FreeBSD VuXML: Documenting security issues in FreeBSD and the FreeBSD Ports Collection

Exim -- remote code execution

Affected packages
4.70 <= exim < 4.80.1

Details

VuXML ID b0f3ab1f-1f3b-11e2-8fe9-0022156e8794
Discovery 2012-10-25
Entry 2012-10-26

This vulnerability affects Exim instances built with DKIM enabled (this is the default for FreeBSD Exim port) and running verification of DKIM signatures on the incoming mail messages.

Phil Penncock reports:

This is a SECURITY release, addressing a CRITICAL remote code execution flaw in versions of Exim between 4.70 and 4.80 inclusive, when built with DKIM support (the default).

This security vulnerability can be exploited by anyone who can send email from a domain for which they control the DNS.

You are not vulnerable if you built Exim with DISABLE_DKIM or if you put this at the start of an ACL plumbed into acl_smtp_connect or acl_smtp_rcpt:

warn control = dkim_disable_verify

References

CVE Name CVE-2012-5671
URL https://lists.exim.org/lurker/message/20121026.080330.74b9147b.en.html