#VU49040 Input validation error in xstream - CVE-2020-26259

Vulnerability identifier: #VU49040

Vulnerability risk: Medium

CVSSv4.0: 7.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:P/U:Green]

CVE-ID: CVE-2020-26259

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: Yes

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

Vendor: XStream

Description

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

The vulnerability exists due to insufficient validation of user-supplied input within the blacklisting feature. A remote attacker can pass specially crafted input to the application and delete arbitrary files on the system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

xstream: 1.4.1 - 1.4.14

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External links
https://github.com/x-stream/xstream/security/advisories/GHSA-jfvx-7wrx-43fh
https://x-stream.github.io/CVE-2020-26259.html

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