CVE-2026-54286 (GCVE-0-2026-54286)

Vulnerability from cvelistv5 – Published: 2026-06-22 17:14 – Updated: 2026-06-23 14:07
VLAI
Title
Hono: Path traversal in `serve-static` on Windows via encoded backslash (`%5C`)
Summary
Hono is a Web application framework that provides support for any JavaScript runtime. Prior to 4.12.25, on Windows hosts, an encoded backslash (%5C) in the request path decodes to \, which the Windows path resolver treats as a separator. serve-static then resolves a single URL segment such as admin\secret.txt into a nested file under the root and serves it, letting an attacker read static files meant to be protected behind prefix-mounted middleware. This vulnerability is fixed in 4.12.25.
Severity
5.9 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-23 14:07 UTC
CWE
  • CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 8129 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
honojs hono Affected: < 4.12.25
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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