Description
A TCP client can perform a TLS handshake and present the server name extension with a server name that is accepted by a server wildcard name, e.g. if the server is configured with a certificate accepting *.example.com, any XYZ.example.com where xyz is a valid name can be used.
Affected products
eclipse: vert.x
References4
- github.com/eclipse-vertx/vert.x/security/advisories/GHSA-3g76-f… ExploitVendor Advisory
- github.com/eclipse-vertx/vert.x/pull/6102 Issue TrackingPatch
- gitlab.eclipse.org/security/vulnerability-reports/-/issues/381 ExploitIssue TrackingThird Party Advisory
- gitlab.eclipse.org/security/vulnerability-reports/-/issues/381 ExploitIssue TrackingThird Party Advisory
Metrics
- CVSS 3.1
-
5.3
MEDIUM
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - CVSS 4.0
-
6.9
MEDIUM
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:L/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: 15 · as of 13 November 2026
- CWE
- CWE-770CWE-295
Could this be exploited in your environment?
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