CVE-2021-22903

Name	CVE-2021-22903
Description	The actionpack ruby gem before 6.1.3.2 suffers from a possible open redirect vulnerability. Specially crafted Host headers in combination with certain "allowed host" formats can cause the Host Authorization middleware in Action Pack to redirect users to a malicious website. This is similar to CVE-2021-22881. Strings in config.hosts that do not have a leading dot are converted to regular expressions without proper escaping. This causes, for example, `config.hosts << "sub.example.com"` to permit a request with a Host header value of `sub-example.com`.
Source	CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
rails (PTS)	bullseye (security), bullseye	2:6.0.3.7+dfsg-2+deb11u2	fixed
	bookworm	2:6.1.7.3+dfsg-2~deb12u1	fixed
	sid, trixie	2:6.1.7.3+dfsg-4	fixed

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
rails	source	(unstable)	(not affected)

Notes

- rails <not-affected> (Vulnerable code introduced in 6.1.0.rc2)
Introduced by: https://github.com/rails/rails/commit/9bc7ea5dab34c8657c91d0258bb5afd8bfcd3a8f (main)
Fixed by: https://github.com/rails/rails/commit/55e0723846aa77ce6afcb677618578fb859b7fd7 (main)