Read the docs
TI-2026-35182 Aliases CVE-2026-47675GHSA-3hrh-pfw6-9m5x

Hono: Cookie helper does not sanitize sameSite and priority, allowing Set-Cookie injection

Priority LOW 23CWE-113Published · Updated

Key facts

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

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and GitHub.

Summary

Hono is a Web application framework that provides support for any JavaScript runtime. Prior to 4.12.21, the serialize() function in hono/cookie validates domain and path options against characters that corrupt Set-Cookie header syntax (;, \r, \n), but does not apply the same validation to sameSite and priority. An application that passes user-controlled input into either option may produce a Set-Cookie response header containing attacker-chosen additional attributes. This vulnerability is fixed in 4.12.21.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00216 12th percentileScored 2026-11-07
Fix Fixed hono (honojs): 4.12.21hono (npm): 4.12.21

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
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 4.12.214.12.21Patch availableCNA
—hono (npm)before 4.12.214.12.21Patch availableGHSA-3hrh-pfw6-9m5x
  • hono Vendorhonojs Affected before 4.12.21 Fixed in 4.12.21 Patch available CNA
  • hono (npm) Vendor— Affected before 4.12.21 Fixed in 4.12.21 Patch available GHSA-3hrh-pfw6-9m5x

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:hono:hono:*:*:*:*:*:node.js:*:*before 4.12.21Vulnerablehonojs
  • cpe:2.3:a:hono:hono:*:*:*:*:*:node.js:*:* Versions before 4.12.21 Vulnerable ·honojs

Remediation

  • Fix · CNA hono (honojs) Fixed in 4.12.21
  • Fix · GHSA-3hrh-pfw6-9m5x hono (npm) Fixed in 4.12.21 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-47675
  2. 2026-10-03 Alias added: GHSA-3hrh-pfw6-9m5x

References

  • TI-2024-21741 Hono vulnerable to Restricted Directory Traversal in serveStatic with deno 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-2026-23190 Hono: Arbitrary file access via serveStatic vulnerability CVSS 3.1CRITICAL 9.8
  • TI-2026-22076 Hono is Vulnerable to Authentication Bypass by IP Spoofing in AWS Lambda ALB conninfo CVSS 3.1HIGH 8.2
  • TI-2026-18334 JWT algorithm confusion in Hono JWK Auth Middleware when JWK lacks "alg" (untrusted header.alg fallback) CVSS 3.1HIGH 8.2
See all 33 →

Sources