CVE-2023-42797: Siemens CP-8031 MASTER MODULE · Use of Uninitialized Resource
Affects Siemens CP-8031 MASTER MODULESource CVE Database V5
Public exploit available · CVSS 6.6 Medium.
Data as of 26 Oct 2026, 14:05 UTC
- EPSS
- 0.5% chance of exploitation in 30 days – higher than 45% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:CExploitation evidence
Disclosed: evidence found.
CVE published 9 Jan 2024
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: evidence found.
CVSS exploit maturity: proof of concept public
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), CVSS vector, the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
AI-suggested
European organizations should take immediate steps to mitigate this vulnerability beyond generic patching advice. First, ensure that all affected Siemens MASTER MODULE devices are identified through asset inventory and version audits. Restrict network access to the network configuration service to trusted administrators only, using network segmentation and firewall rules to limit exposure. Implement strong authentication mechanisms and monitor for unusual configuration uploads or changes. Employ multi-factor authentication (MFA) for all administrative access to reduce the risk of credential compromise. Regularly review device startup logs and configuration change logs for signs of tampering. Siemens users should prioritize upgrading to CPCI85 V05.20 or later versions as soon as patches become available. Until patches are applied, consider deploying intrusion detection systems (IDS) tuned to detect anomalous command injection attempts or unusual network configuration uploads. Additionally, conduct security awareness training for personnel managing these devices to recognize and report suspicious activities. Finally, maintain offline backups of device configurations to enable rapid recovery if compromise occurs.
Description
A vulnerability has been identified in CP-8031 MASTER MODULE (All versions < CPCI85 V05.20), CP-8050 MASTER MODULE (All versions < CPCI85 V05.20). The network configuration service of affected devices contains a flaw in the conversion of ipv4 addresses that could lead to an uninitialized variable being used in succeeding validation steps. By uploading specially crafted network configuration, an authenticated remote attacker could be able to inject commands that are executed on the device with root privileges during device startup.