#VU56064 Out-of-bounds read in OpenSSL - CVE-2021-3712

Vulnerability identifier: #VU56064

Vulnerability risk: Medium

CVSSv4.0: 2.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-3712

CWE-ID: CWE-125

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 potentially sensitive information.

The vulnerability exists due to a boundary condition when processing ASN.1 strings related to a confusion with NULL termination of strings in array. A remote attacker can pass specially crafted data to the application to trigger an out-of-bounds read error and read contents of memory on the system or perform a denial of service (DoS) attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

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

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External links
https://www.openssl.org/news/secadv/20210824.txt
https://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=94d23fcff9b2a7a8368dfe52214d5c2569882c11
https://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=ccb0a11145ee72b042d10593a64eaf9e8a55ec12

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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.