/ 
URI-5.26
⭐ Starred 58 / URI::icap
Security Advisories (1)
CVE-2026-19953 (2026-08-31)

URI versions before 5.36 for Perl encode non-NFC host names to non-standard punycode labels via missing normalization in nameprep. nameprep lowercases each host label but performs no Unicode normalization. IDNA requires a label to be normalized to Form C before it is encoded (RFC 5891), so a label that is not already in NFC is encoded to a different A-label than its normalized form. A label built from the precomposed Devanagari sequence U+0958 U+093E encodes to xn--72b5c without normalization but to xn--11b2fg after NFC normalization, and xn--72b5c does not round-trip back to the original label. Any caller that reads host() from a URI built from untrusted input and uses it for a security decision (an allow or deny list, an SSRF filter, deduplication, a cache key) sees the non-standard label, while a client that fetches the same URL resolves the NFC form, so the check and the fetch can disagree about the host.

NAME

URI::icap - URI scheme for ICAP Identifiers

VERSION

Version 5.20

SYNOPSIS

use URI::icap;

my $uri = URI->new('icap://icap-proxy.example.com/');

DESCRIPTION

This module implements the icap: URI scheme defined in RFC 3507, for the Internet Content Adaptation Protocol.

SUBROUTINES/METHODS

This module inherits the behaviour of URI::http and overrides the default_portdefault_port> method.

default_port

The default port for icap servers is 1344

DIAGNOSTICS

See URI

CONFIGURATION AND ENVIRONMENT

See URI and URI

DEPENDENCIES

None

INCOMPATIBILITIES

None reported

BUGS AND LIMITATIONS

See URI

SEE ALSO

RFC 3507

AUTHOR

David Dick, <ddick at cpan.org>

LICENSE AND COPYRIGHT

Copyright 2016 David Dick.

This program is free software; you can redistribute it and/or modify it under the terms of either: the GNU General Public License as published by the Free Software Foundation; or the Artistic License.

See http://dev.perl.org/licenses/ for more information.