SB2026072195 - Interpretation Conflict in fast-uri



SB2026072195 - Interpretation Conflict in fast-uri

Published: July 21, 2026

Security Bulletin ID SB2026072195
CSH Severity
High
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Remote access
Highest impact Data manipulation

Breakdown by Severity

High 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 vulnerability.


1) Interpretation Conflict (CVE-ID: CVE-2026-13676)

CWE-ID: CWE-436 - Interpretation Conflict

CVSSv4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to modify data on the system.

The vulnerability exists due to fast-uri fail to canonicalize Unicode (IDN) hostnames for HTTP-family URLs. The IDN conversion path calls a helper that does not exist on the global URL constructor, silently leaving the host in its original Unicode form while normalize() and equal() still return values that differ from a WHATWG-compatible URL parser. A remote attacker can trigger the vulnerability to modify data on the system.


Remediation

Install update from vendor's website.