CVE-2026-86253
h3 before 1.15.6 Path Traversal via Percent-Encoded Dot Segments
CVSS Score
5.9
EPSS Score
0.0%
EPSS Percentile
0th
h3 (npm package) versions <= 2.0.1-rc.14 contain a path traversal vulnerability in serveStatic(). On Node.js deployments, event.url.pathname is not normalized, so percent-encoded dot segments (%2e%2e) are passed to decodeURI() and decoded to ../ sequences without sanitization. An unauthenticated remote attacker can send crafted requests to endpoints served by serveStatic() to read arbitrary files outside the intended static directory. Fixed in 1.15.6 and 2.0.1-rc.15.
| CWE | CWE-22 |
| Vendor | h3js |
| Product | h3 |
| Published | Sep 6, 2026 |
| Last Updated | Sep 10, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N Attack Vector
Network
Attack Complexity
High
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None
Affected Versions
h3js / h3
0 < 1.15.6 2.0.0-beta.0 < 2.0.1-rc.15
References
Credits
🔍 0xkakash1