CVE-2026-47675
Hono: Cookie helper does not sanitize sameSite and priority, allowing Set-Cookie injection
CVSS Score
4.3
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-113 CWE-1287 |
| Vendor | honojs |
| Product | hono |
| Published | May 28, 2026 |
| Last Updated | May 28, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
Required
Scope
Unchanged
Confidentiality
None
Integrity
Low
Availability
None
Affected Versions
honojs / hono
< 4.12.21