CVE-2026-108860
BotSharp through 5.2.0 contains an authentication bypass vulnerability that allows unauthenticated…
- Risk score
- 68/100
- CVSS
- 9.1 v3.1
- Exploit chance (30 days)
- 0.5%
- Published
- 11 Oct 2026
Open in the live forecast Today's forecast
What to know
- What it is
- 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 know…
- Affected
- See advisory
- Fix
- Apply the vendor's security update; see the linked advisory.
- Exploitation
- No known exploitation
Why it is Amber
- CVSS 9.1 critical
- Remotely exploitable without logging in
References
- 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
Original description
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.
Last activity 11 Oct 2026. Patch Forecast updates every hour.