CVE-2026-27700 - Vulnerability Analysis

Overview

Hono 4.12.0 and 4.12.1 contain an IP restriction bypass caused by incorrect selection of the first value in the X-Forwarded-For header in hono/aws-lambda behind AWS ALB, letting attackers bypass IP-based access control, exploit requires use behind AWS ALB.

Severity & Score

Impact

Attackers can bypass IP-based access controls, potentially gaining unauthorized access to restricted resources.

Mitigation

Upgrade to version 4.12.2 or later.

References

• https://github.com/honojs/hono/commit/41adbf56e252c04611f8972364ac0887ae07a4c7
• https://github.com/honojs/hono/releases/tag/v4.12.2
• https://github.com/honojs/hono/security/advisories/GHSA-xh87-mx6m-69f3

Related Resources

• Vulnerability Intelligence Dashboard
• Credential Scanner