CVE-2026-55559

CVE-2026-55559 is a Critical (CVSS 9.8) remote code execution vulnerability in Yamcs (mission control framework) prior to versions 5.12.8 and 5.13.2 . The root cause is that templateArgs submitted via POST /api/instances or PATCH /api/instances/{instance} are appended into the rendered YAML confi...

GHSA-9JG3-G3WH-W9PJ Yamcs has Unauthenticated Directory Traversal

Attack type: Unauthenticated remote Impact: Attackers can access any system files from the underlying host. Affected components: HttpRequestHandler.java, StaticFileHandler.java An Unauthenticated Directory Traversal vulnerability exists in Yamcs Steps to Reproduce: 1. Start Yamcs and login as a...

Yamcs has Unauthenticated Directory Traversal

Attack type: Unauthenticated remote Impact: Attackers can access any system files from the underlying host. Affected components: HttpRequestHandler.java, StaticFileHandler.java An Unauthenticated Directory Traversal vulnerability exists in Yamcs Steps to Reproduce: 1. Start Yamcs and login as a...

CVE-2026-55552

Yamcs is a mission control framework affected by an unauthenticated directory traversal in StaticFileHandler.locateFile (yamcs-core). The method resolves request paths without calling Path.normalize and Path.toAbsolutePath to verify the result stays within the configured staticRoots, allowing tra...

EUVD-2026-67842

Yamcs is a mission control framework. Prior to 5.11.13, Yamcs StaticFileHandler.locateFile resolves an unauthenticated request path without using Path.normalize and Path.toAbsolutePath to confirm that the absolute path remains within the configured staticRoots. A path containing traversal segment...

CVE-2026-55552 Yamcs: Unauthenticated Directory Traversal

Yamcs is a mission control framework. Prior to 5.11.13, Yamcs StaticFileHandler.locateFile resolves an unauthenticated request path without using Path.normalize and Path.toAbsolutePath to confirm that the absolute path remains within the configured staticRoots. A path containing traversal segment...

GHSA-RXPG-WJF8-QV9C Yamcs has Reflected XSS in the URL of the Authorize Endpoint

Attack type: Unauthenticated remote Impact: Attackers can execute arbitrary JavaScript in a user's browser, including obtaining a user's session token and refresh token. Affected components: authorize.html, AuthHandler.java, HandlerContext.java A Reflected Cross-Site Scripting vulnerability...

Yamcs has Reflected XSS in the URL of the Authorize Endpoint

Attack type: Unauthenticated remote Impact: Attackers can execute arbitrary JavaScript in a user's browser, including obtaining a user's session token and refresh token. Affected components: authorize.html, AuthHandler.java, HandlerContext.java A Reflected Cross-Site Scripting vulnerability...

EUVD-2026-67841

Yamcs is a mission control framework. Prior to 5.9.4, Yamcs reflects an attacker-controlled redirecturi parameter from GET /auth/authorize into yamcs-core/src/main/resources/auth/templates/authorize.html without adequate HTML escaping by yamcs-core/src/main/java/org/yamcs/http/auth/AuthHandler.ja...

CVE-2026-55549 Yamcs: Reflected XSS in the URL of the Authorize Endpoint

Yamcs is a mission control framework. Prior to 5.9.4, Yamcs reflects an attacker-controlled redirecturi parameter from GET /auth/authorize into yamcs-core/src/main/resources/auth/templates/authorize.html without adequate HTML escaping by yamcs-core/src/main/java/org/yamcs/http/auth/AuthHandler.ja...

CVE-2026-55549

Yamcs , an open-source mission control framework, is vulnerable to reflected cross-site scripting (XSS) in the redirect_uri parameter of the GET /auth/authorize endpoint. The parameter is reflected into authorize.html without adequate HTML escaping by AuthHandler.java and HandlerContext.java , al...

EUVD-2026-44960

Yamcs: Insecure Direct Object Reference IDOR in PacketsApi allows unprivileged users to dump all telemetry packets...

GHSA-CVW4-55PP-3HFQ Yamcs's Missing Authorization on Role and Privilege Enumeration Endpoints Allows Any Authenticated User to Disclose Full Security Configuration

Summary Missing authorization checks on three IAM API endpoints GET /api/roles, GET /api/roles/name, GET /api/privileges allow any authenticated user — regardless of their assigned permissions — to enumerate the complete list of system privileges and role definitions. An attacker with only a...

Yamcs's Missing Authorization on Role and Privilege Enumeration Endpoints Allows Any Authenticated User to Disclose Full Security Configuration

Summary Missing authorization checks on three IAM API endpoints GET /api/roles, GET /api/roles/name, GET /api/privileges allow any authenticated user — regardless of their assigned permissions — to enumerate the complete list of system privileges and role definitions. An attacker with only a...

EUVD-2026-67840

Yamcs is a mission control framework. Prior to 5.12.8 and 5.13.2, Yamcs omits SystemPrivilege.ControlAccess checks from IamApi.listRoles, IamApi.getRole, and IamApi.listPrivileges in yamcs-core/src/main/java/org/yamcs/http/api/IamApi.java. Any authenticated account can call GET /api/roles, GET...

CVE-2026-55547

CVE-2026-55547 affects Yamcs , a mission control framework, in versions prior to 5.12.8 and 5.13.2 . The root cause is missing SystemPrivilege.ControlAccess authorization checks in three IAM API endpoints (GET /api/roles, GET /api/roles/{name}, GET /api/privileges) within IamApi.java. Any authent...

GHSA-FWWW-CP23-7F5G Yamcs's WebSocket subscription handlers omit the privilege checks their REST siblings enforce

Asset / scope: Yamcs 5.12.7 WebSocket topics packets, algorithm-status, mdb-changes Summary Several WebSocket subscription handlers do not perform the privilege check that their REST counterparts enforce, so a principal subscribing over WebSocket receives data the REST API would have scoped or...

Yamcs's WebSocket subscription handlers omit the privilege checks their REST siblings enforce

Asset / scope: Yamcs 5.12.7 WebSocket topics packets, algorithm-status, mdb-changes Summary Several WebSocket subscription handlers do not perform the privilege check that their REST counterparts enforce, so a principal subscribing over WebSocket receives data the REST API would have scoped or...

CVE-2026-55545

CVE-2026-55545 is an authorization bypass in Yamcs , a mission control framework, affecting versions prior to 5.12.8 and 5.13.2 . Three WebSocket subscription handlers fail to enforce the privilege checks their REST counterparts require: PacketsApi.subscribePackets omits the ReadPacket check, Pro...

EUVD-2026-67839

Yamcs is a mission control framework. Prior to 5.12.8 and 5.13.2, Yamcs WebSocket subscription handlers fail to enforce the privileges required by equivalent REST endpoints. PacketsApi.subscribePackets exposes the packets WebSocket topic without ObjectPrivilegeType.ReadPacket,...