#VU58236 Path traversal in SIMATIC PCS 7 and Siemens SIMATIC WinCC - CVE-2021-40359

Vulnerability identifier: #VU58236

Vulnerability risk: Medium

CVSSv4.0: 4.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-40359

CWE-ID: CWE-22

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
SIMATIC PCS 7
Server applications / SCADA systems
Siemens SIMATIC WinCC
Server applications / SCADA systems

Vendor: Siemens

Description

The vulnerability allows a remote attacker to perform directory traversal attacks.

The vulnerability exists due to input validation error when processing directory traversal sequences. A remote authenticated attacker can send a specially crafted HTTP request and read arbitrary files on the system.

Mitigation
Install update from vendor's website.

Vulnerable software versions

SIMATIC PCS 7: 8.2 - 9.1

Siemens SIMATIC WinCC: 7.4 - 17

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External links
https://cert-portal.siemens.com/productcert/pdf/ssa-840188.pdf

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.