CVE-2021-33016: KUKA KR C4 - Use of Hard-Coded Credentials

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.0% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2022-05-26 · updated 2026-06-17
Weakness: CWE-798

Description

An attacker can gain full access (read/write/delete) to sensitive folders due to hard-coded credentials on KUKA KR C4 control software for versions prior to 8.7 or any product running KSS.

Affected products

KUKA Kr C4 Firmware: before 8.7 — fixed in 8.7
KUKA Kss: all versions

How to fix

Upgrade to a fixed version: KUKA Kr C4 Firmware 8.7. Check the vendor advisory for mitigations.

References

https://www.cisa.gov/uscert/ics/advisories/icsa-21-208-01
https://www.cisa.gov/uscert/ics/advisories/icsa-21-208-01

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