CVE-2020-8923: XSS in Dart

Severity: medium (CVSS 6.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-03-26 · updated 2026-06-17
Weakness: CWE-79

Description

An improper HTML sanitization in Dart versions up to and including 2.7.1 and dev versions 2.8.0-dev.16.0, allows an attacker leveraging DOM Clobbering techniques to skip the sanitization and inject custom html/javascript (XSS). Mitigation: update your Dart SDK to 2.7.2, and 2.8.0-dev.17.0 for the dev version. If you cannot update, we recommend you review the way you use the affected APIs, and pay special attention to cases where user-provided data is used to populate DOM nodes. Consider using Element.innerText or Node.text to populate DOM elements.

Affected products

Google LLC Dart SDK: before 2.7.2; 2.8.0-dev0.0, 2.8.0-dev1.0, 2.8.0-dev10.0, 2.8.0-dev11.0, 2.8.0-dev12.0, 2.8.0-dev13.0 (+11) — fixed in 2.7.2

How to fix

Upgrade to a fixed version: Google LLC Dart SDK 2.7.2. Check the vendor advisory for mitigations.

References

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