CVE-2026-84201
appium-mcp-server through 0.1.61 fails to validate or normalize file paths in the write_file and write_files_batch tools, allowing attackers to write files outside the intended PROJECT_ROOT directory.
Does this matter?
Lower severity and a low EPSS score (0.19%). Track it; it rarely justifies an emergency change on its own.
Description
appium-mcp-server through 0.1.61 fails to validate or normalize file paths in the write_file and write_files_batch tools, allowing attackers to write files outside the intended PROJECT_ROOT directory. Attackers can supply absolute paths or relative paths with parent directory segments to overwrite arbitrary files with the server user's privileges, including shell profiles and configuration files in the home directory.
- CVSS 4.0
- 6.9 MEDIUMCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 0.19% probability · 8th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-22
- Source
- disclosure@vulncheck.com
EPSS 0.2% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://github.com/argneshu/appium-mcp-server/blob/92b5c2b325e7bdd124f1f41a6049028b2a44e89c/src/mcp_server.py
- https://github.com/argneshu/appium-mcp-server/blob/92b5c2b325e7bdd124f1f41a6049028b2a44e89c/src/tools/write_files_batch.py
- https://www.npmjs.com/package/appium-mcp-server
- https://www.vulncheck.com/advisories/appium-mcp-server-through-0.1.61-path-traversal-in-write-file-and-write-files-batch
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.