Detect Prettier eslint-config-prettier Embedded Malicious Code (CVE-2025-54313) in Elastic Security
Detects exploitation indicators related to CVE-2025-54313, a supply chain compromise affecting the eslint-config-prettier npm package (Prettier). The package was trojanized with embedded malicious code (CWE-506), enabling arbitrary code execution during npm install or build processes. This vulnerability is listed in CISA's Known Exploited Vulnerabilities catalog.
MITRE ATT&CK
- Tactic
- Initial Access Execution Persistence
Elastic Detection Query
sequence by host.name with maxspan=5m
[process where event.action == "start"
and process.name in ("node", "npm", "npx", "sh", "bash", "powershell.exe", "cmd.exe")
and (process.command_line like "*eslint-config-prettier*" or process.parent.command_line like "*eslint-config-prettier*")]
[any where event.category in ("network", "file")
and (
(event.category == "network" and not network.destination.domain like "*npmjs.org*" and not network.destination.ip like "127.*")
or (event.category == "file" and file.extension in ("exe", "dll", "sh", "ps1", "bat"))
)
]EQL sequence detecting a node/npm process referencing eslint-config-prettier followed within 5 minutes by suspicious file creation or unexpected outbound network connection, indicating malicious payload execution.
Data Sources
Required Tables
False Positives & Tuning
- Development machines installing eslint-config-prettier from a clean source before remediation
- Automated dependency update bots triggering npm installs
- Legitimate post-install scripts in unrelated packages running alongside eslint-config-prettier
Other platforms for CVE-2025-54313
Testing Methodology
Validate this detection against 3 adversary techniques from Atomic Red Team. Each test below lists the behaviour to exercise and the telemetry you should expect to see. Executable commands and cleanup steps are available with Pro.
- Test 1Simulate Malicious postinstall Hook Execution via eslint-config-prettier
Expected signal: EDR should record: npm parent process spawning bash, bash executing malicious.sh, file creation of pwned.txt, outbound network attempt to 127.0.0.1:9999
- Test 2Detect eslint-config-prettier in Installed Node Modules
Expected signal: Process events showing find and python3 spawned from shell; file read events on node_modules/eslint-config-prettier/package.json across filesystem
- Test 3Simulate Outbound Exfiltration from Node Process Post-Install
Expected signal: EDR network telemetry showing node process initiating outbound TCP connection; process command line containing 'process.env' and network connection attempt
Unlock Pro Content
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