CVE-2026-55565: Yamcs

Critical severity, CVSS 9.9. EPSS: 0.7% chance of exploitation in the next 30 days.

Yamcs is a mission control framework. Prior to 5.12.8 and 5.13.2, Yamcs LikeExpression.fillCode_getValueReturn in yamcs-core/src/main/java/org/yamcs/yarch/streamsql/LikeExpression.java inserts an unescaped LIKE pattern into Java source compiled by Expression.getCompiledExpression through SimpleCompiler.cook instead of applying ValueExpression.escapeJavaString. The pattern can originate from POST /api/archive/{instance}:executeSql, POST /api/archive/{instance}:streamSql, POST /api/archive/{instance}/tables/{table}:readRows, GET /api/archive/{instance}/events, or activity searches, including paths available with ReadTables, ReadEvents, or ReadActivities. A quote in the pattern can inject Java that runs as the Yamcs server process. This issue is fixed in versions 5.12.8 and 5.13.2.

Affected products

• Yamcs Yamcs: before 5.12.8 (fixed in 5.12.8); from 5.13.0, before 5.13.2 (fixed in 5.13.2)

Published 2026-08-28. Last modified 2026-09-08.