CVE-2017-3737

NameCVE-2017-3737
DescriptionOpenSSL 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.
SourceCVE (at NVD; CERT, LWN, oss-sec, fulldisc, bugtraq, EDB, Metasploit, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, Mageia, GitHub code/issues, web search, more)
ReferencesDSA-4065-1
NVD severitymedium (attack range: remote)

Vulnerable and fixed packages

The table below lists information on source packages.

Source PackageReleaseVersionStatus
openssl (PTS)jessie1.0.1t-1+deb8u8fixed
jessie (security)1.0.1t-1+deb8u10fixed
stretch1.1.0f-3+deb9u2fixed
stretch (security)1.1.0j-1~deb9u1fixed
buster, sid1.1.1a-1fixed
openssl1.0 (PTS)stretch (security), stretch1.0.2l-2+deb9u3fixed
buster, sid1.0.2q-2fixed

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

PackageTypeReleaseFixed VersionUrgencyOriginDebian Bugs
opensslsource(unstable)1.1.0b-2medium
opensslsourcejessie(not affected)
opensslsourcewheezy(not affected)
openssl1.0source(unstable)1.0.2n-1medium
openssl1.0sourcestretch1.0.2l-2+deb9u2mediumDSA-4065-1

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

Search for package or bug name: Reporting problems