Description
Dragonfly is an in-memory data store built for modern application workloads. Prior to 1.40.0, CMS.INITBYDIM and CMS.INITBYPROB accept dimensions whose width times depth times sizeof(int64_t) overflows in src/core/cms.cc, allocating an undersized counter buffer while CMS.INCRBY and CMS.QUERY use the unbounded dimensions, which allows an unauthenticated remote client to corrupt or disclose adjacent heap memory and crash the server. This issue is fixed in version 1.40.0.
References5
Metrics
- CVSS 4.0
-
8.8
HIGH
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:H/VA:H/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 - EPSS — exploit probability
- 1% percentile: 45 · as of 11 November 2026
- CWE
- CWE-190
Could this be exploited in your environment?
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