#VU1589 Observable discrepancy in OpenSSL - CVE-2016-2178

Vulnerability identifier: #VU1589

Vulnerability risk: Low

CVSSv4.0: 1.1 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2016-2178

CWE-ID: CWE-203

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
OpenSSL
Server applications / Encryption software

Vendor: OpenSSL Software Foundation

Description

The vulnerability allows a local user to perform timing attack.

The vulnerability exists due to an error within the dsa_sign_setup() function in crypto/dsa/dsa_ossl.c. A local user can obtain a DSA private key via a timing side-channel attack.

Mitigation
Install update from vendor's website.

Vulnerable software versions

OpenSSL: before 1.0.1u, 1.0.2i, 1.0.1u, 1.0.1u

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External links
https://bugzilla.redhat.com/show_bug.cgi?id=1343400
https://git.openssl.org/?p=openssl.git;a=commit;h=399944622df7bd81af62e67ea967c470534090e2

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Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.