CVE-2026-50013 — Hoverfly: Process Crash via Concurrent Map Write Race Condition in Diff Mode
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…
Published: 2026-09-11 · CVSS: 7.5 · CVSS 3.1
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.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7