#VU54328 Out-of-bounds write in CODESYS V2 web server - CVE-2021-30193

Vulnerability identifier: #VU54328

Vulnerability risk: High

CVSSv4.0: 8.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2021-30193

CWE-ID: CWE-787

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
CODESYS V2 web server
Server applications / Web servers

Vendor: CODESYS

Description

The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists due to a boundary error when processing untrusted input. A remote attacker can use a specially crafted web server request, trigger out-of-bounds write and execute arbitrary code on the target system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

CODESYS V2 web server: before 1.1.9.20

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External links
https://customers.codesys.com/index.php
https://customers.codesys.com/index.php?eID=dumpFile&t=f&f=14726&token=553da5d11234bbe1ceed59969d419a71bb8c8747&download=

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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.