CVE-2026-50013
Hoverfly: Process Crash via Concurrent Map Write Race Condition in Diff Mode
HIGH 7.5EPSS 0.5%
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.
- Affected
- SpectoLabs · hoverfly
- CVSS v3.1 GITHUB
- 7.5 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - EPSS
- 0.47% chance of exploitation in the next 30 days, 39th percentile
- Published
- 2026-09-11
- Updated
- 2026-09-14