Catalyst::Plugin::Authentication versions before 0.10029 for Perl allow timing attacks on stored passwords via eq comparisons in the legacy password verifier.

CVE-2026-5091 was fixed in the realm-based verifier. The legacy verifier, used by the deprecated login method, compares clear-text passwords, crypt hashes and base64 digests with eq, so the comparison time depends on how many leading bytes match.

A remote attacker can use response-time differences to guess the stored password or hash.

Catalyst::Plugin::Authentication versions before 0.10029 for Perl allow timing attacks on stored passwords via eq comparisons in the legacy password verifier.

CVE-2026-5091 was fixed in the realm-based verifier. The legacy verifier, used by the deprecated login method, compares clear-text passwords, crypt hashes and base64 digests with eq, so the comparison time depends on how many leading bytes match.

A remote attacker can use response-time differences to guess the stored password or hash.

Affected: Ubuntu:16.04:LTS: libcatalyst-plugin-authentication-perl, Ubuntu:18.04:LTS: libcatalyst-plugin-authentication-perl, Ubuntu:20.04:LTS: libcatalyst-plugin-authentication-perl, Ubuntu:22.04:LTS: libcatalyst-plugin-authentication-perl, Ubuntu:24.04:LTS: libcatalyst-plugin-authentication-perl, Ubuntu:26.10: libcatalyst-plugin-authentication-perl, Ubuntu:26.04:LTS: libcatalyst-plugin-authentication-perl

Catalyst::Plugin::Authentication versions before 0.10029 for Perl allow timing attacks on stored passwords via eq comparisons in the legacy password verifier. CVE-2026-5091 was fixed in the realm-based verifier. The legacy verifier, used by the deprecated login method, compares clear-text passwords, crypt hashes and base64 digests with eq, so the comparison time depends on how many leading bytes match. A remote attacker can use response-time differences to guess the stored password or hash.