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VULNERABILITIES

CVE-2026-50013 Details

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.

Metrics

CVSS 3.x Severity and Vector Strings:

CNA: [email protected]CVSS-B:7.5 HIGHVector:CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References to Advisories, Solutions, and Tools

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URLSource(s)Tag(s)
https://github.com/SpectoLabs/hoverfly/pull/1227 [email protected]
https://github.com/SpectoLabs/hoverfly/releases/tag/v1.12.8 [email protected]
https://github.com/SpectoLabs/hoverfly/security/advisories/GHSA-qrh4-p6v4-mrfg [email protected]

Weakness Enumeration

CWE-IDCWE NameSource
CWE-362Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')[email protected]
CWE-820Missing Synchronization[email protected]

Affected Products

No affected product data is available for this CVE.

Change History

2 change records found show changes

QUICK INFO

CVE Dictionary Entry:
CVE-2026-50013
NVD Published Date:
Sep 11, 2026
NVD Last Modified:
Sep 14, 2026
Source:
[email protected]
CVE-2026-50013 Details - Not Deferred