CVE-2026-77021Missing decompression size limit in agent receiver allows memory exhaustion via push agent data
Updated under an hour ago ()
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It affects Checkmk GmbH Checkmk. Add what you run to find out whether that includes you.
No exploitation reported and no EPSS estimate yet.
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Improper handling of highly compressed data (data amplification) in Checkmk <2.5.0p14, <2.4.0p37, <2.3.0p51 and 2.2.0 (EOL) allows an attacker who controls a host registered for push mode to exhaust the memory of the agent receiver by sending a small zlib compressed payload that decompresses to an arbitrary size.
- CVSS
- 5.3 MEDIUM (v4.0, CNA)CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
- Weakness (CWE)
- CWE-409
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- Checkmk
- NVD analysis
- Deferred
- Record last updated
- Sep 21, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
Checkmk GmbH Checkmk checkmk:checkmk (from the name) | from 2.5.0 before 2.5.0p14; from 2.4.0 before 2.4.0p37; from 2.3.0 before 2.3.0p51; 2.2.0 | CNA record |
References
- https://checkmk.com/werk/22116vendor-advisory
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.