Improper Handling of Alternate Encoding in Wildfly Elytron - CVE-2026-19611
Published: September 15, 2026
Vulnerability identifier: #VU150032
CSH Severity: Medium
CVSS v4: 9.1 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-19611
CWE-ID: CWE-173
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to gain unauthorized access to affected accounts.
The vulnerability exists due to improper handling of alternate encoding in password hashing and verification when normalizing passwords with Unicode NFKC. A remote attacker can use an ASCII-only dictionary to guess passwords intended to contain fullwidth non-ASCII characters to gain unauthorized access to affected accounts.
The issue affects passwords containing characters subject to NFKC compatibility folding.
Affected software
Wildfly Elytron
How to mitigate CVE-2026-19611
Install security update from vendor's website.
Wildfly Elytron - addressed in versions 2.6.10 SP1, 2.8.5, 2.9.2 SP1