#VU23451 Cryptographic issues in OpenSSL - CVE-2019-1551

Vulnerability identifier: #VU23451

Vulnerability risk: Low

CVSSv4.0: 1.7 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2019-1551

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 gain access to sensitive information.

The vulnerability exists due to an overflow issue within the rsaz_512_sqr(): the x64_64 Montgomery squaring procedure used in exponentiation with 512-bit moduli. A remote attacker can perform an attack against DH512 keys.

Mitigation
Install update from vendor's website.

Vulnerable software versions

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

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External links
https://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=419102400a2811582a7a3d4a4e317d72e5ce0a8f
https://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=f1c5eea8a817075d31e43f5876993c6710238c98
https://www.openssl.org/news/secadv/20191206.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.