Vulnerability identifier: #VU51243

Vulnerability risk: Medium

CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-27217

CWE-ID: CWE-125

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
yubihsm-shell
Universal components / Libraries / Programming Languages & Components

Vendor: Yubico

Description

The vulnerability allows a remote attacker to perform denial of service (DoS) attack.

The vulnerability exists due to a boundary condition when validating the length of authenticated messages during device communication. A remote attacker can send specially crafted data to the system and cause the yubihsm library to fail with a “Not enough space” error.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

yubihsm-shell: 1.0.0 - 2021.03

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External links
http://www.yubico.com/support/security-advisories/ysa-2021-01/

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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.