#VU56685 Use of a broken or risky cryptographic algorithm in Libgcrypt - CVE-2021-40528

Vulnerability identifier: #VU56685

Vulnerability risk: Medium

CVSSv4.0: 4.6 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-40528

CWE-ID: CWE-327

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Libgcrypt
Client/Desktop applications / Encryption software

Vendor: GNU

Description

The vulnerability allows a remote attacker to gain access to potentially sensitive information.

The vulnerability exists due to use of a broken or risky cryptographic algorithm in the ElGamal implementation. A remote attacker can gain unauthorized access to sensitive information on the system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Libgcrypt: 1.2.3 - 1.9.3

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External links
https://ibm.github.io/system-security-research-updates/2021/07/20/insecurity-elgamal-pt1
https://ibm.github.io/system-security-research-updates/2021/09/06/insecurity-elgamal-pt2
https://eprint.iacr.org/2021/923

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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.