Vulnerability · Published Oct 14, 2026 · Assigned by eclipse

CVE-2026-102479

High 8.7

In plain English

A high-severity security flaw in Eclipse Vert.x from Eclipse Foundation. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 27% of all known vulnerabilities).

Severity (CVSS 4.0)8.7High
Exploit odds (30 days)0.3%top 73.0% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

In Eclipse Vert.x versions [5.0.0,5.0.12] or [5.1.0,5.1.9] or [5.2.0, 5.2.0], the Vert.x HTTP/1.x decoder uses a canonicalization for well known HTTP headers, the canonicalization process interprets well crafted headers as headers of this list, allowing for instance Content-Xength to be interpeted as Content-Length. This can be exploited for request smuggling purpose. The impacted component is io.vertx:vertx-core.

Affected products (as reported)

VendorProductVersions
Eclipse Foundation Eclipse Vert.x 5.0.0 – through 5.0.125.1.0 – through 5.1.95.2.0

Weakness: CWE-444 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N

References