#VU110694 Input validation error in YAML-LibYAML - CVE-2025-40908

Vulnerability identifier: #VU110694

Vulnerability risk: Medium

CVSSv4.0: 1 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2025-40908

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
YAML-LibYAML
Other software / Other software solutions

Vendor: TINITA

Description

The vulnerability allows a remote attacker to overwrite arbitrary files on the system.

The vulnerability exists due to insufficient validation of user-supplied input in LoadFile method. A remote attacker can pass specially crafted arguments to the affected method and overwrite arbitrary files on the system. 

Mitigation
Install updates from vendor's website.

Vulnerable software versions

YAML-LibYAML: 0.01 - 0.902.0

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External links
https://github.com/ingydotnet/yaml-libyaml-pm/issues/120
https://github.com/ingydotnet/yaml-libyaml-pm/pull/121
https://github.com/ingydotnet/yaml-libyaml-pm/pull/122

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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.