#VU55303 Unchecked Return Value in libyang - CVE-2021-28904

Vulnerability identifier: #VU55303

Vulnerability risk: Medium

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-28904

CWE-ID: CWE-252

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
libyang
Universal components / Libraries / Libraries used by multiple products

Vendor: CESNET

Description

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

The vulnerability exists due to an unchecked return value in the "ext_get_plugin()" function. A remote attacker can run a specially crafted program to cause a denial of service condition.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

libyang: 1.0.109 - 1.0.225

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External links
https://github.com/CESNET/libyang/issues/1451

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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.