CVE-2026-27700

8.2 HIGH
Published: February 25, 2026 Modified: March 02, 2026
View on NVD

Description

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.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
https://github.com/honojs/hono/releases/tag/v4.12.2
Source: security-advisories@github.com
Product Release Notes
https://github.com/honojs/hono/security/advisories/GHSA-xh87-mx6m-69f3
Source: security-advisories@github.com
Vendor Advisory

3 reference(s) from NVD

Quick Stats

CVSS v3 Score
8.2 / 10.0
EPSS (Exploit Probability)
0.0%
5th percentile
Exploitation Status
Not in CISA KEV

Affected Vendors

hono