CVE-2026-108860

BotSharp through 5.2.0 contains an authentication bypass vulnerability that allows unauthenticated remote attackers to forge bearer tokens using the hard-coded Jwt:Key in WebStarter appsettings.json. Attackers can sign tokens with the committed HMAC secret and fixed botsharp issuer and audience to impersonate any known user, including administrators, on Authorize-protected API routes.

CVSS v3 9.1 CRITICAL

9.1^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/SciSharp/BotSharp
https://github.com/SciSharp/BotSharp/blob/a11ee0317cab5c619df1cb5d0c4fc39d1b6e30b4/src/Infrastructure/BotSharp.OpenAPI/BotSharpOpenApiExtensions.cs#L46-L57
https://github.com/SciSharp/BotSharp/blob/a11ee0317cab5c619df1cb5d0c4fc39d1b6e30b4/src/WebStarter/appsettings.json#L16-L20
https://hackmd.io/@1ExmmukzRMWN7B4gQ4W-4Q/scisharp-botsharp-public-jwt-signing-key
https://www.vulncheck.com/advisories/botsharp-through-5.2.0-authentication-bypass-via-hard-coded-jwt-signing-key

Configurations

No configuration.

History

11 Oct 2026, 14:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-11 14:17

Updated : 2026-10-16 19:18

NVD link : CVE-2026-108860

Mitre link : CVE-2026-108860

CVE.ORG link : CVE-2026-108860

JSON object : View

Products Affected

No product.

CWE

CWE-321

Use of Hard-coded Cryptographic Key

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