CVE-2017-7418

Name	CVE-2017-7418
Description	ProFTPD before 1.3.5e and 1.3.6 before 1.3.6rc5 controls whether the home directory of a user could contain a symbolic link through the AllowChrootSymlinks configuration option, but checks only the last path component when enforcing AllowChrootSymlinks. Attackers with local access could bypass the AllowChrootSymlinks control by replacing a path component (other than the last one) with a symbolic link. The threat model includes an attacker who is not granted full filesystem access by a hosting provider, but can reconfigure the home directory of an FTP user.
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	859592

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
proftpd-dfsg (PTS)	jessie, jessie (lts)	1.3.5e+r1.3.5-2+deb8u8	fixed
	stretch (security)	1.3.5e+r1.3.5b-4+deb9u2	fixed
	stretch (lts), stretch	1.3.5e+r1.3.5b-4+deb9u3	fixed
	buster	1.3.6-4+deb10u6	fixed
	buster (security), buster (lts)	1.3.6-4+deb10u4	fixed
	bullseye	1.3.7a+dfsg-12+deb11u2	fixed
	bookworm	1.3.8+dfsg-4+deb12u3	fixed
	sid	1.3.8.b+dfsg-3	fixed

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
proftpd-dfsg	source	jessie	1.3.5-1.1+deb8u2
proftpd-dfsg	source	(unstable)	1.3.5b-4	low		859592

Notes

[wheezy] - proftpd-dfsg <no-dsa> (Minor issue)
http://bugs.proftpd.org/show_bug.cgi?id=4295
https://github.com/proftpd/proftpd/commit/ecff21e0d0e84f35c299ef91d7fda088e516d4ed
https://github.com/proftpd/proftpd/commit/f59593e6ff730b832dbe8754916cb5c821db579f