CVE-2017-3732 Information

Description

There is a carry propagating bug in the x86_64 Montgomery squaring procedure in OpenSSL 1.0.2 before 1.0.2k and 1.1.0 before 1.1.0d. No EC algorithms are affected. Analysis suggests that attacks against RSA and DSA as a result of this defect would be very difficult to perform and are not believed likely. Attacks against DH are considered just feasible (although very difficult) because most of the work necessary to deduce information about a private key may be performed offline. The amount of resources required for such an attack would be very significant and likely only accessible to a limited number of attackers. An attacker would additionally need online access to an unpatched system using the target private key in a scenario with persistent DH parameters and a private key that is shared between multiple clients. For example this can occur by default in OpenSSL DHE based SSL/TLS ciphersuites. Note: This issue is very similar to CVE-2015-3193 but must be treated as a separate problem.

CVSS Vector

CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

Reference

http://www.oracle.com/technetwork/security-advisory/cpujan2018-3236628.html http://www.oracle.com/technetwork/security-advisory/cpujul2017-3236622.html http://www.oracle.com/technetwork/security-advisory/cpuoct2017-3236626.html http://www.securityfocus.com/bid/95814 http://www.securitytracker.com/id/1037717 https://access.redhat.com/errata/RHSA-2018:2185 https://access.redhat.com/errata/RHSA-2018:2186 https://access.redhat.com/errata/RHSA-2018:2187 https://access.redhat.com/errata/RHSA-2018:2568 https://access.redhat.com/errata/RHSA-2018:2575 https://access.redhat.com/errata/RHSA-2018:2713 https://github.com/openssl/openssl/commit/a59b90bf491410f1f2bc4540cc21f1980fd14c5b https://security.FreeBSD.org/advisories/FreeBSD-SA-17:02.openssl.asc https://security.gentoo.org/glsa/201702-07 https://support.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbhf03838en_us https://www.openssl.org/news/secadv/20170126.txt https://www.oracle.com/technetwork/security-advisory/cpuapr2019-5072813.html https://www.tenable.com/security/tns-2017-04

Attack Complexity

HIGH

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

HIGH

Availability Impact

NONE

Base Score

NONE

Base Severity

5.9