CVE-2019-1547

Name	CVE-2019-1547
Description	Normally in OpenSSL EC groups always have a co-factor present and this is used in side channel resistant code paths. However, in some cases, it is possible to construct a group using explicit parameters (instead of using a named curve). In those cases it is possible that such a group does not have the cofactor present. This can occur even where all the parameters match a known named curve. If such a curve is used then OpenSSL falls back to non-side channel resistant code paths which may result in full key recovery during an ECDSA signature operation. In order to be vulnerable an attacker would have to have the ability to time the creation of a large number of signatures where explicit parameters with no co-factor present are in use by an application using libcrypto. For the avoidance of doubt libssl is not vulnerable because explicit parameters are never used. Fixed in OpenSSL 1.1.1d (Affected 1.1.1-1.1.1c). Fixed in OpenSSL 1.1.0l (Affected 1.1.0-1.1.0k). Fixed in OpenSSL 1.0.2t (Affected 1.0.2-1.0.2s).
Source	CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)
References	DLA-1932-1, DSA-4539-1, DSA-4540-1, ELA-171-1

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
openssl (PTS)	jessie, jessie (lts)	1.0.1t-1+deb8u21	fixed
	stretch (security)	1.1.0l-1~deb9u6	fixed
	stretch (lts), stretch	1.1.0l-1~deb9u9	fixed
	buster (security), buster, buster (lts)	1.1.1n-0+deb10u6	fixed
	bullseye	1.1.1w-0+deb11u1	fixed
	bullseye (security)	1.1.1w-0+deb11u2	fixed
	bookworm	3.0.15-1~deb12u1	fixed
	bookworm (security)	3.0.14-1~deb12u2	fixed
	sid, trixie	3.3.2-2	fixed
openssl1.0 (PTS)	stretch (security)	1.0.2u-1~deb9u7	fixed
	stretch (lts), stretch	1.0.2u-1~deb9u9	fixed

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

Package	Type	Release	Fixed Version	Origin
openssl	source	wheezy	1.0.1t-1+deb7u9	ELA-171-1
openssl	source	jessie	1.0.1t-1+deb8u12	DLA-1932-1
openssl	source	stretch	1.1.0l-1~deb9u1	DSA-4539-1
openssl	source	buster	1.1.1d-0+deb10u1	DSA-4539-1
openssl	source	(unstable)	1.1.1d-1
openssl1.0	source	stretch	1.0.2t-1~deb9u1	DSA-4540-1
openssl1.0	source	(unstable)	(unfixed)

Notes

https://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=21c856b75d81eff61aa63b4f036bb64a85bf6d46 (OpenSSL_1_0_2t)
https://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=7c1709c2da5414f5b6133d00a03fc8c5bf996c7a (OpenSSL_1_1_0l)
https://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=30c22fa8b1d840036b8e203585738df62a03cec8 (OpenSSL_1_1_1d)
https://www.openssl.org/news/secadv/20190910.txt