Description
In Eclipse Vert.x versions [4.0.0, 4.5.34] or [5.0.0,5.0.12] or [5.1.0,5.1.9] or [5.2.0, 5.2.0], the WebSocket implementation does not define a maximum number of bytes allocation when decompressing frames or messages. This can be used to implement DDOS attacks with a zip bomb. The impacted component is io.vertx:vertx-core.
Affected products
eclipse: vert.x
References2
- github.com/eclipse-vertx/vert.x/security/advisories/GHSA-h722-h… Vendor Advisory
- gitlab.eclipse.org/security/cve-assignment/-/work_items/341 Issue TrackingThird Party Advisory
Metrics
- CVSS 3.1
-
5.9
MEDIUM
Score source: NVD
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H - CVSS 4.0
-
8.7
HIGH
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/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
- 0% percentile: 18 · as of 10 November 2026
- CWE
- CWE-770
Could this be exploited in your environment?
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