GHSA-55p7-v223-x366 IdentityServer Open Redirect vulnerability
Attackers can craft malicious URLs that IdentityServer incorrectly treats as trusted, redirecting users to untrusted third-party sites.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is GHSA-55p7-v223-x366?
GHSA-55p7-v223-x366 is a vulnerability in IdentityServer4, published on 31 Jul 2024. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
Impact
It is possible for an attacker to craft malicious Urls that certain functions in IdentityServer will incorrectly treat as local and trusted. If such a Url is returned as a redirect, some browsers will follow it to a third-party, untrusted site.
Affected Methods
In the
DefaultIdentityServerInteractionService, theGetAuthorizationContextAsyncmethod may return non-null and theIsValidReturnUrlmethod may return true for malicious Urls, indicating incorrectly that they can be safely redirected to.UI code calling these two methods is the most commonly used code path that will expose the vulnerability. The default UI templates rely on this behavior in the Login, Challenge, and Consent pages. Customized user interface code might also rely on this behavior. The following uncommonly used APIs are also vulnerable:
The
ServerUrlExtensions.GetIdentityServerRelativeUrl,ReturnUrlParser.ParseAsyncandOidcReturnUrlParser.ParseAsyncmethods may incorrectly return non-null, and theReturnUrlParser.IsValidReturnUrlandOidcReturnUrlParser.IsValidReturnUrlmethods may incorrectly return true for malicious Urls.
Patches
IdentityServer4 is no longer supported and will not be receiving updates. Please consider updating to Duende.IdentityServer.
Which versions are affected by GHSA-55p7-v223-x366?
2 open source packages ship an affected version, including IdentityServer4.
| Package | Affected | Fixed in |
|---|---|---|
IdentityServer4 NuGet | All versions to 4.1.2 | None |
IdentityServer4 NuGet | All versions to 4.1.2 | None |
How do I fix GHSA-55p7-v223-x366?
No fix has been published for GHSA-55p7-v223-x366 yet. Limit exposure of the affected software until one is available.
Is GHSA-55p7-v223-x366 being exploited?
There is no known exploitation of GHSA-55p7-v223-x366 in the wild and no public exploit code.