CVE-2026-39847
Published April 8, 2026 · Updated April 8, 2026
What This Means
CVE-2026-39847 is a critical path traversal vulnerability in the Emmett web framework, affecting versions from 2.5.0 to before 2.8.1. An attacker can exploit this flaw to read sensitive files outside the intended assets directory by leveraging "../" sequences in URLs. To mitigate this risk, upgrade to Emmett version 2.8.1 or later immediately.
Official Description+
Emmett is a full-stack Python web framework designed with simplicity. From 2.5.0 to before 2.8.1, the RSGI static handler for Emmett's internal assets (/__emmett__ paths) is vulnerable to path traversal attacks. An attacker can use ../ sequences (eg /__emmett__/../rsgi/handlers.py) to read arbitrary files outside the assets directory. This vulnerability is fixed in 2.8.1.
Recommended Actions
- Check if your systems use any of the affected products listed above.
- Apply vendor patches immediately if available.
- Monitor vendor advisories for updates and additional mitigations.
- Review logs for indicators of compromise related to CVE-2026-39847.