CVE-2022-43551

Name	CVE-2022-43551
Description	A vulnerability exists in curl <7.87.0 HSTS check that could be bypassed to trick it to keep using HTTP. Using its HSTS support, curl can be instructed to use HTTPS instead of using an insecure clear-text HTTP step even when HTTP is provided in the URL. However, the HSTS mechanism could be bypassed if the host name in the given URL first uses IDN characters that get replaced to ASCII counterparts as part of the IDN conversion. Like using the character UTF-8 U+3002 (IDEOGRAPHIC FULL STOP) instead of the common ASCII full stop (U+002E) `.`. Then in a subsequent request, it does not detect the HSTS state and makes a clear text transfer. Because it would store the info IDN encoded but look for it IDN decoded.
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	1026829

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
curl (PTS)	bullseye	7.74.0-1.3+deb11u13	vulnerable
	bullseye (security)	7.74.0-1.3+deb11u14	vulnerable
	bookworm	7.88.1-10+deb12u8	fixed
	bookworm (security)	7.88.1-10+deb12u5	fixed
	sid, trixie	8.11.1-1	fixed

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
curl	source	buster	(not affected)
curl	source	(unstable)	7.86.0-3			1026829

Notes

[bullseye] - curl <ignored> (curl is not built with HSTS support)
[buster] - curl <not-affected> (Vulnerable code not present)
https://curl.se/docs/CVE-2022-43551.html
Introduced by: https://github.com/curl/curl/commit/7385610d0c74c6a254fea5e4cd6e1d559d848c8c (curl-7_74_0)
Enabled by default since: https://github.com/curl/curl/commit/d71ff2b9db566b3f4b2eb29441c2df86715d4339 (curl-7_77_0)
Fixed by: https://github.com/curl/curl/commit/9e71901634e276dd050481c4320f046bebb1bc28 (curl-7_87_0)