Description
Hono is a Web application framework that provides support for any JavaScript runtime. Prior to 4.12.12, a discrepancy between browser cookie parsing and parse() handling allows cookie prefix protections to be bypassed. Cookie names that are treated as distinct by the browser may be normalized to the same key by parse(), allowing attacker-controlled cookies to override legitimate ones. This vulnerability is fixed in 4.12.12.
Affected products
hono: hono
References3
- github.com/honojs/hono/security/advisories/GHSA-r5rp-j6wh-rvv4 Vendor Advisory
- github.com/honojs/hono/commit/cc067c85592415cb1880ad3c61ed92347… Third Party Advisory
- github.com/honojs/hono/releases/tag/v4.12.12 Release Notes
Metrics
- CVSS 3.1
-
4.8
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N - EPSS — exploit probability
- 0% percentile: 22 · as of 12 November 2026
- CWE
- CWE-20
Could this be exploited in your environment?
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