CVE-2026-55552

highpriority · track · 1EPSS 0.017 · 77 %ileUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
1.72% (77th) EPSS
CVSS 7.5 · high
Is it mine?
1 products
Check your exposure
Who says so?
1 sources
osv

EPSS · scored 2026-10-27

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.

01

cvss

Technical severity, 0–10. One row per scoring source.

7.5
010

base score 0–10 · higher = more severe · hover a vector to decode

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:Nsecondary · security-advisories@github.comexploitability 3.9 · impact 3.6
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:Nsecondary · OSV
v3.17.3highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N/E:Fsecondary · CVSS-BT (t0sche)
02

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS
03

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-22USCWE-22US
04

affected products (1)

Products and version ranges known to be affected.

05

advisories (1)

Vendor and ecosystem advisories describing this.

  • GHSA-9jg3-g3wh-w9pjYamcs has Unauthenticated Directory Traversal2026-08-28ghsa · osvUS

    ### 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 <=5.8.6, allowing anyone to access any file on the underlying operating system. This allows unauthenticated attackers to download sensitive files and data. <img width="2170" height="1289" alt="image" src="https://github.com/user-attachments/assets/8d426da1-5351-4240-a290-8d858be61312" /> ## Steps to Reproduce: 1. Start Yamcs and login as a user 2. Paste the following URL in the browser and press enter: ``` http://localhost:8090//etc/passwd ``` 3. The `/etc/passwd` file will be downloaded. ## Acknowledgements This vulnerability was discovered by Abderrahim Dahmani while solving a STARPWN 2025 CTF challenge at DEFCON 33 offered by VisionSpace Technologies.

06

sources

Which sources assert this record, and when.

osvNVDCVE.orgMITRE
published 2026-08-28modified 2026-08-31
07

references (5) nvd

External citations — patches, advisories, analysis.

scry

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