CVE-2025-58123: Checkmk · Improper Certificate Validation
Source CVE Database V5
Not known to be exploited · CVSS 6.9 Medium.
Data as of 26 Oct 2026, 10:12 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 1% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:H/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 28 Aug 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
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), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
AI-suggested
Organizations should immediately review their use of the Checkmk Exchange BGP Monitoring plugin and assess exposure to MitM attack vectors, such as unsecured or untrusted network segments. Until a patch is available, network administrators should enforce strict network segmentation and use VPNs or encrypted tunnels to protect monitoring traffic. Implementing certificate pinning or manual certificate validation where possible can reduce risk. Monitoring network traffic for unusual TLS certificate anomalies or unexpected certificate authorities can help detect exploitation attempts. Additionally, organizations should keep abreast of Checkmk vendor advisories for patches or updates addressing this vulnerability and apply them promptly once released. Conducting penetration tests or red team exercises simulating MitM attacks on monitoring infrastructure can validate the effectiveness of mitigations. Finally, reviewing and hardening overall TLS configurations and ensuring up-to-date cryptographic libraries in the monitoring environment will further reduce risk.
Description
Improper Certificate Validation in Checkmk Exchange plugin BGP Monitoring allows attackers in MitM position to intercept traffic.