Inconsistent interpretation of HTTP requests in Vert.x - CVE-2026-102479
Published: November 10, 2026
Vulnerability identifier: #VU164373
CSH Severity: Medium
CVSS v4: 8.7 [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]
CVE-ID: CVE-2026-102479
CWE-ID: CWE-444
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to smuggle HTTP requests and compromise request integrity.
The vulnerability exists due to incorrect header canonicalization in the Vert.x HTTP/1.x decoder when processing crafted HTTP headers. A remote attacker can send requests containing Content-Xength headers that are incorrectly interpreted as Content-Length to manipulate request boundaries and smuggle requests.
Affected software
Vert.x
How to mitigate CVE-2026-102479
Install security update from vendor's website.
Vert.x - addressed in versions 5.1.10, 5.2.1