GHSA-c9w5-qp6m-m395 CVE-2026-9094 GO-2026-5953
Casdoor: GetTokenExchangeToken bypass through lack of cross-organization JWT signature check
- Severity
- 9.8 / 10
- Critical · CVSS 3.1
- Exploit chance (EPSS)
- 0.42%
- Chance of exploitation in the next 30 days. Higher than 36.32% of scored vulnerabilities.
- Known exploited
- No
- Not in CISA's catalog
- Fix
2.387.0- Upgrade github.com/casdoor/casdoor to this version or later
Description
Casdoor versions 2.362.0 and earlier contain a vulnerability enabling cross-organization token exchange. The GetTokenExchangeToken function in object/token_oauth.go validates JWT signatures but does not verify that the token's user belongs to the same organization as the target application. This can result in privilege escalation across organizational boundaries.
Affected versions
Go
| Package | Vulnerable | Fixed in |
|---|---|---|
| github.com/casdoor/casdoor | < 2.387.0 |
2.387.0 |
| github.com/casdoor/casdoor | all versions |
No fix yet |
How to fix
Move to the fixed version or later with your package manager, update the lockfile, and run your tests. If the package only arrives through another dependency, upgrade that dependency first. If none of its releases pulls a fixed version yet, force the version with your package manager's override.
github.com/casdoor/casdoor Go → 2.387.0
- go
go get github.com/casdoor/casdoor@v2.387.0 && go mod tidy
Severity breakdown
CVSS 3.1 9.8
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Weakness
CWE-269: Improper Privilege Management
The product does not properly assign, modify, track, or check privileges for an actor, creating an unintended sphere of control for that actor.
How to prevent it
- Architecture and Design, Operation: Very carefully manage the setting, management, and handling of privileges. Explicitly manage trust zones in the software.
- Architecture and Design: Follow the principle of least privilege when assigning access rights to entities in a software system.
- Architecture and Design: Consider following the principle of separation of privilege. Require multiple conditions to be met before permitting access to a system resource.
CWE-863: Incorrect Authorization
The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check.
How to prevent it
- Architecture and Design: Divide the product into anonymous, normal, privileged, and administrative areas. Reduce the attack surface by carefully mapping roles with data and functionality. Use role-based access control (RBAC) [REF-229] to enforce the roles at the appropriate boundaries. Note that this approach may not protect against horizontal authorization, i.e., it will not protect a user from attacking others with the same role.
- Architecture and Design: Ensure that access control checks are performed related to the business logic. These checks may be different than the access control checks that are applied to more generic resources such as files, connections, processes, memory, and database records. For example, a database may restrict access for medical records to a specific database user, but each record might only be intended to be accessible to the patient and the patient's doctor [REF-7].
- Architecture and Design: Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, consider using authorization frameworks such as the JAAS Authorization Framework [REF-233] and the OWASP ESAPI Access Control feature [REF-45].
- Architecture and Design: For web applications, make sure that the access control mechanism is enforced correctly at the server side on every page. Users should not be able to access any unauthorized functionality or information by simply requesting direct access to that page. One way to do this is to ensure that all pages containing sensitive information are not cached, and that all such pages restrict access to requests that are accompanied by an active and authenticated session token associated with a user who has the required permissions to access that page.
- System Configuration, Installation: Use the access control capabilities of your operating system and server environment and define your access control lists accordingly. Use a "default deny" policy when defining these ACLs.
References
Advisories
Packages
Other links
Timeline
- Published
- Last updated by the source
- Latest EPSS score
Related advisories
| Advisory | Severity | Why it's related |
|---|---|---|
| GHSA-mfvp-7p3v-x9mh Casdoor SAML callback handler accepts any well-formed SAMLResponse sent to /api/acs without verifying that it corresponds to an AuthnRequest | Critical | Also affects github.com/casdoor/casdoor |
| GHSA-339w-3hqm-9pjc Casdoor doesn't verify that a JWT used for token exchange is still active | Critical | Also affects github.com/casdoor/casdoor |
| GHSA-rgq2-93gj-ffxg Casdoor doesn't enforce SAML assertion time bounds | High | Also affects github.com/casdoor/casdoor |
| GHSA-3w4h-g9f5-j84p Casdoor does not validate the AudienceRestriction element in SAML assertions | Critical | Also affects github.com/casdoor/casdoor |
| GHSA-gv4m-v8c8-hr3g Casdoor allows users to bypass configured MFA requirements | Medium | Also affects github.com/casdoor/casdoor |
| GHSA-fwgq-j9r9-qjgr Casdoor has an authentication bypass | Critical | Also affects github.com/casdoor/casdoor |
| GHSA-rmxx-v9rj-vpvg Casdoor: Arbitrary file write possible through Local File System storage provider | Medium | Also affects github.com/casdoor/casdoor |
| GHSA-p8c7-hjc4-gwf8 Casdoor vulnerable to SSRF via crafted Webhook URL | High | Also affects github.com/casdoor/casdoor |
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