CVE-2017-3737

Name	CVE-2017-3737
Description	OpenSSL 1.0.2 (starting from version 1.0.2b) introduced an "error state" mechanism. The intent was that if a fatal error occurred during a handshake then OpenSSL would move into the error state and would immediately fail if you attempted to continue the handshake. This works as designed for the explicit handshake functions (SSL_do_handshake(), SSL_accept() and SSL_connect()), however due to a bug it does not work correctly if SSL_read() or SSL_write() is called directly. In that scenario, if the handshake fails then a fatal error will be returned in the initial function call. If SSL_read()/SSL_write() is subsequently called by the application for the same SSL object then it will succeed and the data is passed without being decrypted/encrypted directly from the SSL/TLS record layer. In order to exploit this issue an application bug would have to be present that resulted in a call to SSL_read()/SSL_write() being issued after having already received a fatal error. OpenSSL version 1.0.2b-1.0.2m are affected. Fixed in OpenSSL 1.0.2n. OpenSSL 1.1.0 is not affected.
Source	CVE (at NVD; CERT, LWN, oss-sec, fulldisc, bugtraq, EDB, Metasploit, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, Mageia, GitHub code/issues, web search, more)
References	DSA-4065-1
NVD severity	medium

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
openssl (PTS)	stretch (security), stretch	1.1.0l-1~deb9u1	fixed
	buster, buster (security)	1.1.1d-0+deb10u3	fixed
	bullseye, sid	1.1.1g-1	fixed
openssl1.0 (PTS)	stretch	1.0.2u-1~deb9u1	fixed
	stretch (security)	1.0.2u-1~deb9u2	fixed

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

Package	Type	Release	Fixed Version	Origin
openssl	source	wheezy	(not affected)
openssl	source	jessie	(not affected)
openssl	source	(unstable)	1.1.0b-2
openssl1.0	source	stretch	1.0.2l-2+deb9u2	DSA-4065-1
openssl1.0	source	(unstable)	1.0.2n-1

Notes

[jessie] - openssl <not-affected> (Issue introduced in 1.0.2b)
[wheezy] - openssl <not-affected> (Issue introduced in 1.0.2b)
Not fully correct tracking, the issue just does not affect OpenSSL 1.1.0
thus mark as fixed in the first 1.1.0 version which entered unstable.
https://www.openssl.org/news/secadv/20171207.txt
OpenSSL_1_0_2-stable: https://git.openssl.org/?p=openssl.git;a=commit;h=898fb884b706aaeb283de4812340bb0bde8476dc
1.0.2b introduced a hardening mechanism designed to protect against bugs
in application code. This CVE applies to the hardening mechanism being
incomplete. OpenSSL versions older than 1.0.2b don't have the hardening
mechanism at all.
Hardening mechanism introduced in:
https://git.openssl.org/?p=openssl.git;a=commit;h=e4f77bf1833245d2b6aa4ce6a16c85e1cdf78589