Remote code execution in Libgcrypt

1) Heap-based buffer overflow

EUVDB-ID: #VU50150

Risk: High

CVSSv3.1: 7.9 [CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C]

CVE-ID: CVE-2021-3345

CWE-ID: CWE-122 - Heap-based Buffer Overflow

Exploit availability: Yes

Description

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to a boundary error within the _gcry_md_block_write(0 function in cipher/hash-common.c in Libgcrypt. A remote attacker can pass specially crafted data to the application, trigger heap-based buffer overflow and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Libgcrypt: 1.9.0

External links

http://bugs.gentoo.org/show_bug.cgi?id=767814
http://git.gnupg.org/cgi-bin/gitweb.cgi?p=libgcrypt.git;a=commit;h=512c0c75276949f13b6373b5c04f7065af750b08
http://gnupg.org
http://lists.gnupg.org/pipermail/gnupg-announce/2021q1/000455.html
http://lists.gnupg.org/pipermail/gnupg-announce/2021q1/000456.html

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. However, proof of concept for this vulnerability is available.