CVE-2026-19953: URI versions before 5.36 for Perl encode non-NFC host names to non-standard punycode labels via missing normalization in nameprep

Overview

Severity

Medium (CVSS 6.5)

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N/E:U

Exploit Status

Not Exploited

Patch Tuesday

2026-Aug

Released

2026-09-03

EPSS Score

0.37% (percentile: 30.3%)

Affected Products (1)

Other

• 21781-17084

Security Updates (1)

• Security Update

Revision History

• 2026-09-03: Information published.