#VU54016 Resource exhaustion in Siemens products - CVE-2021-31340

Vulnerability identifier: #VU54016

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-2021-31340

CWE-ID: CWE-400

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
SIMATIC RF166C
Server applications / SCADA systems
SIMATIC RF185C
Hardware solutions / Routers & switches, VoIP, GSM, etc
SIMATIC RF186C
Hardware solutions / Routers & switches, VoIP, GSM, etc
SIMATIC RF186CI
Hardware solutions / Routers & switches, VoIP, GSM, etc
SIMATIC RF188C
Hardware solutions / Routers & switches, VoIP, GSM, etc
SIMATIC RF188CI
Hardware solutions / Routers & switches, VoIP, GSM, etc
SIMATIC RF360R
Hardware solutions / Firmware
SIMATIC RF615R
Hardware solutions / Firmware
SIMATIC RF680R
Hardware solutions / Firmware
SIMATIC RF685R
Hardware solutions / Firmware

Vendor: Siemens

Description

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

The vulnerability exists due to application does not properly control consumption of internal resources. A remote attacker can trigger resource exhaustion and perform a denial of service (DoS) attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

SIMATIC RF166C: 1.1

SIMATIC RF185C: 1.1

SIMATIC RF186C: 1.1

SIMATIC RF186CI: 1.1

SIMATIC RF188C: 1.1

SIMATIC RF188CI: 1.1

SIMATIC RF360R: All versions

SIMATIC RF615R: before 3.0

SIMATIC RF680R: before 3.0

SIMATIC RF685R: before 3.0

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External links
https://cert-portal.siemens.com/productcert/pdf/ssa-787292.pdf
https://us-cert.cisa.gov/ics/advisories/icsa-21-159-13

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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.