Description
Umbraco CMS before 17.7.2 and 18.2.2 contains an authentication bypass vulnerability that allows unauthenticated attackers to register attacker-controlled OAuth redirect URIs by poisoning the Host header. Attackers send signed-in users authorization links using response_mode=form_post to capture codes, then redeem them via HTTP Basic client credentials to hijack back-office sessions and execute code through Razor templates.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
umbraco Umbraco-CMS
Default version status: unaffected
0 to < 17.7.2affected18.0.0 to < 18.2.2affected
pkg:nuget/Umbraco.CmsReferences
- https://github.com/umbraco/Umbraco-CMS/commit/490b9b27dcbb8fb3fe868a36203590968b0569d6 ↗
- https://github.com/umbraco/Umbraco-CMS ↗
- https://github.com/umbraco/Umbraco-CMS/security/advisories/GHSA-rpv9-qp4c-g469 ↗
- https://github.com/umbraco/Umbraco-CMS/blob/release-18.2.1/src/Umbraco.Cms.Api.Management/Middleware/BackOfficeAuthorizationInitializationMiddleware.cs#L74-L112 ↗
- https://www.vulncheck.com/advisories/umbraco-cms-before-17.7.2-and-18.2.2-account-takeover-via-host-header-poisoning ↗