SB2026061978 - Input validation error in React Router
Published: June 19, 2026
Security Bulletin ID
SB2026061978
CSH Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Remote access
Highest impact
Data manipulation
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Input validation error (CVE-ID: CVE-2026-40181)
CWE-ID: CWE-20 - Improper input validation
CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
The vulnerability allows a remote attacker to redirect users to an external domain.
The vulnerability exists due to improper input validation in the redirect function when processing URLs with a path starting with // that is reinterpreted as a protocol-relative URL. A remote attacker can supply a crafted URL to redirect users to an external domain.
This does not affect applications using declarative mode.
Remediation
Install update from vendor's website.