steveiliop56 tinyauth up to 5.0.4 GenericOAuthService VerifyCode race condition

CVSS Meta Temp Score
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CTI Interest Score
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6.1$0-$5k0.00

Summaryinfo

A vulnerability was found in steveiliop56 tinyauth up to 5.0.4 and classified as problematic. This affects the function VerifyCode of the component GenericOAuthService/GithubOAuthService/GoogleOAuthService. Such manipulation leads to race condition. This vulnerability is referenced as CVE-2026-33544. It is possible to launch the attack remotely. No exploit is available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in steveiliop56 tinyauth up to 5.0.4. Affected by this issue is the function VerifyCode of the component GenericOAuthService/GithubOAuthService/GoogleOAuthService. The manipulation with an unknown input leads to a race condition vulnerability. Using CWE to declare the problem leads to CWE-362. The product contains a code sequence that can run concurrently with other code, and the code sequence requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence that is operating concurrently. Impacted is confidentiality, integrity, and availability. CVE summarizes:

Tinyauth is an authentication and authorization server. Prior to version 5.0.5, all three OAuth service implementations (GenericOAuthService, GithubOAuthService, GoogleOAuthService) store PKCE verifiers and access tokens as mutable struct fields on singleton instances shared across all concurrent requests. When two users initiate OAuth login for the same provider concurrently, a race condition between VerifyCode() and Userinfo() causes one user to receive a session with the other user's identity. This issue has been patched in version 5.0.5.

The advisory is available at github.com. This vulnerability is handled as CVE-2026-33544 since 03/20/2026. The exploitation is known to be difficult. The attack may be launched remotely. Successful exploitation requires user interaction by the victim. Technical details are known, but there is no available exploit.

Upgrading to version 5.0.5 eliminates this vulnerability. The upgrade is hosted for download at github.com. Applying the patch f26c2171610d5c2dfbba2edb6ccd39490e349803 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.1
VulDB Meta Temp Score: 6.1

VulDB Base Score: 4.6
VulDB Temp Score: 4.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.7
CNA Vector (GitHub_M): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Race condition
CWE: CWE-362
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: tinyauth 5.0.5
Patch: f26c2171610d5c2dfbba2edb6ccd39490e349803

Timelineinfo

03/20/2026 CVE reserved
04/02/2026 +12 days Advisory disclosed
04/02/2026 +0 days VulDB entry created
04/02/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-9q5m-jfc4-wc92
Status: Confirmed

CVE: CVE-2026-33544 (🔒)
GCVE (CVE): GCVE-0-2026-33544
GCVE (VulDB): GCVE-100-354890

Entryinfo

Created: 04/02/2026 17:25
Changes: 04/02/2026 17:25 (68)
Complete: 🔍
Cache ID: 216:377:103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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