{"api_version":"1","generated_at":"2026-09-11T01:02:38+00:00","cve":"CVE-2026-55559","urls":{"html":"https://cve.report/CVE-2026-55559","api":"https://cve.report/api/cve/CVE-2026-55559.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-55559","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-55559"},"summary":{"title":"Yamcs: Remote Code Execution via instance-template argument YAML injection (createInstance)","description":"Yamcs is a mission control framework. Prior to 5.12.8 and 5.13.2, Yamcs inserts templateArgs from POST /api/instances and PATCH /api/instances/{instance} into YAML through VarStatement.append in yamcs-core/src/main/java/org/yamcs/templating/VarStatement.java without YAML-context escaping. The rendered configuration is parsed by YamcsServer.createInstance and loaded by YamcsServerInstance, allowing an attacker to inject a services entry for org.yamcs.ProcessRunner. 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