title: Incorrect parsing of the backslash characters in Dart library
description: The implementation of backslash parsing in the Dart URI class for versions prior to 2.18 and Flutter versions prior to 3.30 differs from the WhatWG URL standards. Dart uses the RFC 3986 syntax, which creates incompatibilities with the '\' characters in URIs, which can lead to auth bypass in webapps interpreting URIs. We recommend updating Dart or Flutter to mitigate the issue.
problem types: CWE-20 Improper Input Validation
affected:
{
vendor: Google LLC
product: Dart
versions:
version: stable, status: affected, lessThan: 2.18.2, versionType: custom
version: Flutter, status: affected, lessThan: 3.3.3, versionType: custom
platforms: all
}
metrics:
cvssV3_1: [
version: 3.1
vectorString: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
attackVector: NETWORK
attackComplexity: LOW
privilegesRequired: NONE
userInteraction: NONE
scope: UNCHANGED
confidentialityImpact: HIGH
integrityImpact: HIGH
availabilityImpact: HIGH
baseScore: 9.8
baseSeverity: CRITICAL
]