SB2026092920 - Double Decoding of the Same Data in hono

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Main Vulnerability Database SB2026092920

SB2026092920 - Double Decoding of the Same Data in hono

Published: September 29, 2026 Updated: September 30, 2026

Security Bulletin ID SB2026092920
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Remote access
Highest impact Information disclosure

Breakdown by Severity

Medium 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 vulnerability.


1) Double Decoding of the Same Data (CVE-ID: N/A)

CWE-ID: CWE-174 - Double Decoding of the Same Data

CVSSv4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to bypass middleware protections for static files.

The vulnerability exists due to double decoding of the request path in the serveStatic middleware when handling a malformed percent-encoded request path. A remote attacker can send a crafted request that is routed as one path and resolved as another to bypass middleware protections for static files.

Only applications that mount middleware on a portion of the directory served by serveStatic are affected; files remain resolved within the configured root.


Remediation

Install update from vendor's website.

References