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TI-2026-39188 Aliases CVE-2026-54288GHSA-rv63-4mwf-qqc2

Hono: Body Limit Middleware can be bypassed on AWS Lambda by understating `Content-Length`

Priority LOW 34CWE-345Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
Low · Low · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-345.

Summary

Hono is a Web application framework that provides support for any JavaScript runtime. Prior to 4.12.25, the Body Limit Middleware trusts the request's Content-Length header to decide whether a body is within the limit. On AWS Lambda (API Gateway v1/v2, ALB, VPC Lattice, and Lambda@Edge) the body is delivered fully buffered and the adapter builds the request with the client-declared Content-Length, which need not match the actual payload. A client can declare a tiny Content-Length while sending a much larger body, slipping past the limit. This vulnerability is fixed in 4.12.25.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00147 3rd percentileScored 2026-11-07
Fix Fixed hono (honojs): 4.12.25hono (npm): 4.12.25

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
honojshonobefore 4.12.254.12.25Patch availableCNA
—hono (npm)before 4.12.254.12.25Patch availableGHSA-rv63-4mwf-qqc2
  • hono Vendorhonojs Affected before 4.12.25 Fixed in 4.12.25 Patch available CNA
  • hono (npm) Vendor— Affected before 4.12.25 Fixed in 4.12.25 Patch available GHSA-rv63-4mwf-qqc2

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:hono:hono:*:*:*:*:*:*:*:*——honojs
  • cpe:2.3:a:hono:hono:*:*:*:*:*:*:*:* Versions — — ·honojs

Remediation

  • Fix · CNA hono (honojs) Fixed in 4.12.25
  • Fix · GHSA-rv63-4mwf-qqc2 hono (npm) Fixed in 4.12.25 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-54288
  2. 2026-10-03 Alias added: GHSA-rv63-4mwf-qqc2

References

Advisory 1

Other 2

  • TI-2024-21741 Hono vulnerable to Restricted Directory Traversal in serveStatic with deno CVSS 3.1MEDIUM 5.3
  • TI-2024-15441 @hono/node-server can't handle "double dots" in URL CVSS 3.1MEDIUM 5.3
  • TI-2024-32610 Hono vulnerable to bypass of CSRF Middleware by a request without Content-Type header. CVSS 3.1MEDIUM 5.9
  • TI-2024-29381 Hono CSRF middleware can be bypassed using crafted Content-Type header CVSS 3.1MEDIUM 5.0
  • TI-2026-39189 Hono: Lambda@Edge adapter keeps only the last value of a repeated request header, dropping the rest CVSS 3.1MEDIUM 4.8
  • TI-2026-23190 Hono: Arbitrary file access via serveStatic vulnerability CVSS 3.1CRITICAL 9.8
See all 59 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences