{"id":"CVE-2026-55552","aliases":["EUVD-2026-67842","GHSA-9jg3-g3wh-w9pj"],"status":"published","title":"Yamcs: Unauthenticated Directory Traversal","description":"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 segments can escape the intended web root and return an arbitrary readable host file. The flaw is in yamcs-core/src/main/java/org/yamcs/http/StaticFileHandler.java and can disclose sensitive operating-system and application data. This issue is fixed in version 5.11.13, and the 5.12 line is fixed from version 5.12.0.","severity":{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-09","score":0.01722,"percentile":0.77655,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-22"],"published":"2026-08-28T17:18:45Z","modified":"2026-10-28T10:52:14Z","exploits":[{"source":"nuclei","id":"CVE-2026-55552","title":"Yamcs \u003c=5.11.12 - Arbitrary File Read","type":"detection template","url":"https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2026/CVE-2026-55552.yaml"}],"fixes":[{"ecosystem":"Maven","package":"org.yamcs:yamcs-core","fixed_in":["5.11.13","5.12.0"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"Maven","package":"org.yamcs:yamcs-core","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.11.13"}]}]},{"source":"osv","ecosystem":"Maven","package":"org.yamcs:yamcs-core","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.12.0"}]}],"versions":["0.29.3","0.30.0","3.0.0","3.1.0","3.1.1","3.1.2","3.2.0","3.2.1","3.2.2","3.3.0","3.3.1","3.4.0","3.4.1","3.4.11","3.4.2","3.4.3","3.4.4","3.4.5","3.4.6","3.4.8","4.0.0","4.0.1","4.1.1","4.1.2","4.10.0","4.10.1","4.10.2","4.10.3","4.10.4","4.10.5","4.10.6","4.10.7","4.10.8","4.10.9","4.2.0","4.2.1","4.2.2","4.3.0","4.3.1","4.4.0","4.4.1","4.4.2","4.5.0","4.6.0","4.6.1","4.6.2","4.6.3","4.7","4.7.1","4.7.3","4.8.0","4.8.1","4.9.0","4.9.1","4.9.2","4.9.3","4.9.4","5.0.0","5.1.0","5.1.1","5.1.2","5.1.3","5.1.4","5.10.0","5.10.1","5.10.10","5.10.11","5.10.12","5.10.2","5.10.3","5.10.4","5.10.5","5.10.6","5.10.7","5.10.8","5.10.9","5.11.0","5.11.1","5.11.10","5.11.11","5.11.12","5.11.13","5.11.2","5.11.3","5.11.4","5.11.5","5.11.6","5.11.7","5.11.8","5.11.9","5.2.0","5.2.1","5.2.2","5.2.3","5.2.4","5.2.5","5.2.6","5.3.0","5.3.1","5.3.2","5.3.3","5.3.4","5.3.5","5.3.6","5.4.0","5.4.1","5.4.2","5.4.3","5.4.4","5.4.5","5.5.0","5.5.1","5.5.2","5.5.3","5.5.4","5.5.5","5.5.6","5.5.7","5.6.0","5.6.1","5.6.2","5.7.0","5.7.1","5.7.10","5.7.11","5.7.12","5.7.13","5.7.2","5.7.3","5.7.4","5.7.5","5.7.6","5.7.7","5.7.8","5.7.9","5.8.0","5.8.1","5.8.2","5.8.3","5.8.4","5.8.5","5.8.6","5.8.7","5.8.8","5.9.0","5.9.1","5.9.10","5.9.11","5.9.12","5.9.2","5.9.3","5.9.4","5.9.5","5.9.6","5.9.7","5.9.8","5.9.8.1","5.9.9"]}],"products":[{"vendor":"yamcs","product":"yamcs"}],"references":[{"url":"https://github.com/yamcs/yamcs/security/advisories/GHSA-9jg3-g3wh-w9pj","tags":["x_refsource_CONFIRM","advisory","web"]},{"url":"https://github.com/yamcs/yamcs/commit/c7dfd24e469ae1086c23e0fe04401cb1ce4260d4","tags":["x_refsource_MISC","fix","web"]},{"url":"https://github.com/yamcs/yamcs/commit/f4bc588880c166849e983aa8f65b9c8107d06091","tags":["x_refsource_MISC","fix","web"]},{"url":"https://github.com/yamcs/yamcs/releases/tag/yamcs-5.11.13","tags":["x_refsource_MISC","web"]},{"url":"https://github.com/yamcs/yamcs/releases/tag/yamcs-5.12.0","tags":["x_refsource_MISC","web"]},{"url":"https://github.com/advisories/GHSA-9jg3-g3wh-w9pj"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/55xxx/CVE-2026-55552.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-55552","tags":["advisory"]},{"url":"https://github.com/yamcs/yamcs","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2026-55552","title":"Yamcs: Unauthenticated Directory Traversal","description":"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 segments can escape the intended web root and return an arbitrary readable host file. The flaw is in yamcs-core/src/main/java/org/yamcs/http/StaticFileHandler.java and can disclose sensitive operating-system and application data. This issue is fixed in version 5.11.13, and the 5.12 line is fixed from version 5.12.0.","status":"published","published":"2026-08-28T17:18:45.617Z","modified":"2026-08-31T18:54:23.899Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high","assessor":"cna"}],"cwes":["CWE-22"],"updated_at":"2026-11-02T14:20:11.925815Z"}],"euvd":[{"id":"EUVD-2026-67842","description":"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 segments can escape the intended web root and return an arbitrary readable host file. The flaw is in yamcs-core/src/main/java/org/yamcs/http/StaticFileHandler.java and can disclose sensitive operating-system and application data. This issue is fixed in version 5.11.13, and the 5.12 line is fixed from version 5.12.0.","status":"published","published":"2026-08-28T17:18:45Z","modified":"2026-08-31T18:54:23Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high"}],"updated_at":"2026-11-02T18:01:19.818565Z"}],"ghsa":[{"id":"GHSA-9jg3-g3wh-w9pj","title":"Yamcs has Unauthenticated Directory Traversal","description":"### Attack type: \nUnauthenticated remote  \n\n### Impact: \nAttackers can access any system files from the underlying host.\n\n### Affected components: HttpRequestHandler.java, StaticFileHandler.java\n\nAn Unauthenticated Directory Traversal vulnerability exists in Yamcs \u003c=5.8.6, allowing anyone to access any file on the underlying operating system. This allows unauthenticated attackers to download sensitive files and data.\n\n\u003cimg width=\"2170\" height=\"1289\" alt=\"image\" src=\"https://github.com/user-attachments/assets/8d426da1-5351-4240-a290-8d858be61312\" /\u003e\n\n## Steps to Reproduce:\n1. Start Yamcs and login as a user\n2. Paste the following URL in the browser and press enter:\n\n```\nhttp://localhost:8090//etc/passwd\n```\n\n3. The `/etc/passwd` file will be downloaded.\n\n## Acknowledgements\nThis vulnerability was discovered by Abderrahim Dahmani while solving a STARPWN 2025 CTF challenge at DEFCON 33 offered by VisionSpace Technologies.","status":"published","published":"2026-08-28T17:20:42Z","modified":"2026-08-28T17:20:43Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high"}],"cwes":["CWE-22"],"updated_at":"2026-11-02T14:41:07.031507Z"}],"nvd":[{"id":"CVE-2026-55552","description":"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 segments can escape the intended web root and return an arbitrary readable host file. The flaw is in yamcs-core/src/main/java/org/yamcs/http/StaticFileHandler.java and can disclose sensitive operating-system and application data. This issue is fixed in version 5.11.13, and the 5.12 line is fixed from version 5.12.0.","status":"published","published":"2026-08-28T20:18:28.793Z","modified":"2026-09-08T21:08:37.32Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high","assessor":"secondary"}],"cwes":["CWE-22"],"updated_at":"2026-11-02T14:12:42.366888Z"}],"osv":[{"id":"CVE-2026-55552","title":"Yamcs: Unauthenticated Directory Traversal","description":"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 segments can escape the intended web root and return an arbitrary readable host file. The flaw is in yamcs-core/src/main/java/org/yamcs/http/StaticFileHandler.java and can disclose sensitive operating-system and application data. This issue is fixed in version 5.11.13, and the 5.12 line is fixed from version 5.12.0.","status":"published","published":"2026-08-28T17:18:45.617Z","modified":"2026-10-28T10:52:14.291009057Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high"}],"cwes":["CWE-22"],"updated_at":"2026-11-02T15:45:11.22012Z"},{"id":"GHSA-9jg3-g3wh-w9pj","title":"Yamcs has Unauthenticated Directory Traversal","description":"### Attack type: \nUnauthenticated remote  \n\n### Impact: \nAttackers can access any system files from the underlying host.\n\n### Affected components: HttpRequestHandler.java, StaticFileHandler.java\n\nAn Unauthenticated Directory Traversal vulnerability exists in Yamcs \u003c=5.8.6, allowing anyone to access any file on the underlying operating system. This allows unauthenticated attackers to download sensitive files and data.\n\n\u003cimg width=\"2170\" height=\"1289\" alt=\"image\" src=\"https://github.com/user-attachments/assets/8d426da1-5351-4240-a290-8d858be61312\" /\u003e\n\n## Steps to Reproduce:\n1. Start Yamcs and login as a user\n2. Paste the following URL in the browser and press enter:\n\n```\nhttp://localhost:8090//etc/passwd\n```\n\n3. The `/etc/passwd` file will be downloaded.\n\n## Acknowledgements\nThis vulnerability was discovered by Abderrahim Dahmani while solving a STARPWN 2025 CTF challenge at DEFCON 33 offered by VisionSpace Technologies.","status":"published","published":"2026-08-28T17:20:42Z","modified":"2026-08-28T17:40:35.592571Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high"}],"cwes":["CWE-22"],"updated_at":"2026-11-02T15:46:43.875515Z"}]}}