Vulnerability identifier: #VU21043

Vulnerability risk: Low

CVSSv3.1: 3.2 [CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2019-1547

CWE-ID: CWE-310

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
OpenSSL
Server applications / Encryption software

Vendor: OpenSSL Software Foundation

Description

The vulnerability allows a remote attacker to decrypt traffic.

The vulnerability exists due to insufficient enforcement of side channel resistant code paths. A remote attacker with ability to create a large number of signatures, where explicit parameters with no co-factor is present, can force the application to fall back to non-side channel resistant code pathsduring ECDSA signature operation and perform full key recovery.

Successful exploitation of the vulnerability may allow an attacker to decrypt communication between server and client.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

OpenSSL: 1.0.2h - 1.0.2p, 1.1.0h - 1.1.0, 1.1.1c - 1.1.1

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External links
http://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=21c856b75d81eff61aa63b4f036bb64a85bf6d46
http://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=30c22fa8b1d840036b8e203585738df62a03cec8
http://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=7c1709c2da5414f5b6133d00a03fc8c5bf996c7a
http://www.openssl.org/news/secadv/20190910.txt

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

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