CVE-2020-35680

Name	CVE-2020-35680
Description	smtpd/lka_filter.c in OpenSMTPD before 6.8.0p1, in certain configurations, allows remote attackers to cause a denial of service (NULL pointer dereference and daemon crash) via a crafted pattern of client activity, because the filter state machine does not properly maintain the I/O channel between the SMTP engine and the filters layer.
Source	CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)
Debian Bugs	978039

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
opensmtpd (PTS)	buster, buster (security)	6.0.3p1-5+deb10u4	vulnerable
	bullseye	6.8.0p2-3	fixed
	bookworm	6.8.0p2-4	fixed
	trixie, sid	7.4.0p1-1	fixed

The information below is based on the following data on fixed versions.

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
opensmtpd	source	stretch	(not affected)
opensmtpd	source	(unstable)	6.8.0p2-1			978039

Notes

[buster] - opensmtpd <no-dsa> (Minor issue)
[stretch] - opensmtpd <not-affected> (new filter grammar support added in ec69ed85b6c)
https://github.com/openbsd/src/commit/6c3220444ed06b5796dedfd53a0f4becd903c0d1
https://www.mail-archive.com/misc@opensmtpd.org/msg05188.html