#VU17860 Use of a broken or risky cryptographic algorithm in OpenSSL - CVE-2019-1559

Vulnerability identifier: #VU17860

Vulnerability risk: Low

CVSSv4.0: 0.5 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2019-1559

CWE-ID: CWE-327

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 sensitive information.

The vulnerability exists due to the way an application behaves, when it receives a 0-byte record with invalid padding compared to the record with an invalid MAC, which results in padding oracle. A remote attacker can decrypt data.

Successful exploitation of the vulnerability requires that the application is using "non-stitched" ciphersuites and calls SSL_shutdown() twice (first, via a BAD_RECORD_MAC and again via a CLOSE_NOTIFY). 

Mitigation
Install updates from vendor's website.

Vulnerable software versions

OpenSSL: 1.0.2q - 1.0.2p

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External links
https://www.openssl.org/news/secadv/20190226.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.