CVE-2026-33456: Checkmk · Improper Neutralization of Delimiters
Affects CheckmkSource CVE Database V5
Not known to be exploited · CVSS 5.1 Medium : upgrade to 2.5.0b4 or 2.4.0p26 when convenient.
Data as of 30 Oct 2026, 06:59 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 9% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 2.5.0b4, 2.4.0p26
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 10 Apr 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: 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 29 Oct 2026.
What to do
Upgrade Checkmk to 2.5.0b4 or 2.4.0p26.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Checkmk GmbHCheckmk | Affected
| Fixed in
|
| Checkmk GmbHCheckmk | Affected
| Fixed in
|
AI-suggested
If you cannot patch yet, restrict access to the notification test page to trusted users only and monitor for suspicious activity related to Livestatus commands.
Description
Livestatus injection in the notification test mode in Checkmk <2.5.0b4 and <2.4.0p26 allows an authenticated user with access to the notification test page to inject arbitrary Livestatus commands via a crafted service description.