CVE-2026-50013
Description
Hoverfly is an open source API simulation tool. Prior to version 1.12.8, when Hoverfly is running in Diff mode, the `AddDiff()` function writes to the shared `responsesDiff` map without any synchronization (no mutex). When multiple proxy requests are processed concurrently (the normal case for any proxy), the concurrent map writes trigger Go's built-in race detector which causes a `fatal error: concurrent map read and map write`, immediately killing the entire Hoverfly process. This is trivially exploitable by sending multiple simultaneous requests. Version 1.12.8 patches the issue.
How to fix
- github.com/SpectoLabs/hoverfly1.12.8 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| github.com/SpectoLabs/hoverflyGo | v < 1.12.8 | 1.12.8 |
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