This affects anyone passing unsanitised data to Leaf's variable tags. Before this fix, Leaf would not escape any strings passed to tags as variables. If an attacker managed to find a variable that was rendered with their unsanitised data, they could inject scripts into a generated Leaf page, which could enable XSS attacks if other mitigations such as a Content Security Policy were not enabled.
This has been patched in 1.3.0
Sanitise any untrusted input before passing it to Leaf and enable a CSP to block inline script and CSS data.
https://github.com/vapor/leaf-kit-ghsa-rv3x-xq3r-8j9h/pull/1
If you have any questions or comments about this advisory: * Open an issue in Leaf Kit * Email us at security@vapor.codes
{ "nvd_published_at": "2021-08-09T20:15:00Z", "cwe_ids": [ "CWE-79", "CWE-80" ], "severity": "MODERATE", "github_reviewed": true, "github_reviewed_at": "2023-06-09T19:32:32Z" }