CVE-2026-77021
🔶 mediumSummary
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 Score
-
EPSS Score
0.2
Exploit Probability
Published Date
2026-09-21
First Seen: 2026-09-24
🎯 CISA SSVC Assessment Updated: Sep 21, 2026
🔍 Exploitation Status
None
No known exploits
⚙️ Automatable
NO
Requires human interaction
💥 Technical Impact
Partial
Limited system impact
🏆 Discovered By
Sven Jäger (SySS GmbH) (reporter)
SSVC data provided by
CISA
Last Modified
2026-09-21
Source
NVD 🔗
CVSS Vector 4.0
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CWE IDs (Weakness Types)