{"id":"CVE-2026-50013","sourceIdentifier":"security-advisories@github.com","published":"2026-09-11T22:16:37.813","lastModified":"2026-09-30T19:57:08.043","vulnStatus":"Deferred","cveTags":[],"descriptions":[{"lang":"en","value":"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":[{"source":"security-advisories@github.com","affectedData":[{"vendor":"SpectoLabs","product":"hoverfly","versions":[{"version":"< 1.12.8","status":"affected"}]}]}],"metrics":{"cvssMetricV31":[{"source":"security-advisories@github.com","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":7.5,"baseSeverity":"HIGH","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"},"exploitabilityScore":3.9,"impactScore":3.6}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2026-09-14T17:06:19.894343Z","id":"CVE-2026-50013","options":[{"exploitation":"none"},{"automatable":"yes"},{"technicalImpact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}]},"weaknesses":[{"source":"security-advisories@github.com","type":"Secondary","description":[{"lang":"en","value":"CWE-362"},{"lang":"en","value":"CWE-820"}]}],"references":[{"url":"https://github.com/SpectoLabs/hoverfly/pull/1227","source":"security-advisories@github.com"},{"url":"https://github.com/SpectoLabs/hoverfly/releases/tag/v1.12.8","source":"security-advisories@github.com"},{"url":"https://github.com/SpectoLabs/hoverfly/security/advisories/GHSA-qrh4-p6v4-mrfg","source":"security-advisories@github.com"}]}