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 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.

Affected

yamcs

CVSS v3.1 GITHUB

7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

EPSS

1.72% chance of exploitation in the next 30 days, 77th percentile

Nuclei

high · CWE-22

Published

2026-08-28

Updated

2026-08-31

Proof-of-concept exploits (1)

• advisories/GHSA-9jg3-g3wh-w9pj

Nuclei templates (1)

• projectdiscovery/nuclei-templates/blob/main/http/cves/2026/CVE-2026-55552.yaml

References

• CVE Record
• NVD entry