CVE-2026-27700

Summary

Hono is a Web application framework that provides support for any JavaScript runtime. In versions 4.12.0 and 4.12.1, when using the AWS Lambda adapter (hono/aws-lambda) behind an Application Load Balancer (ALB), the getConnInfo() function incorrectly selected the first value from the X-Forwarded-For header. Because AWS ALB appends the real client IP address to the end of the X-Forwarded-For header, the first value can be attacker-controlled. This could allow IP-based access control mechanisms (such as the ipRestriction middleware) to be bypassed. Version 4.12.2 patches the issue.

Affected Software

VendorProductVersion RangeStatus
honojshono>= 4.12.0, < 4.12.2affected

Weaknesses

  • CWE-345: CWE-345: Insufficient Verification of Data Authenticity
  • CWE-290: CWE-290: Authentication Bypass by Spoofing

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: yes
    • Technical Impact: partial

References