Description
Hono before 4.12.7 allows __proto__ key in parseBody with dot option enabled, permitting specially crafted form field names to create objects with __proto__ properties. When parsed results are merged into regular JavaScript objects using unsafe merge patterns, attackers can exploit this to achieve prototype pollution and modify object behavior.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Hono | Hono | < 4.12.7 | 4.12.7 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Wolfi
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Wolfi rolling | langfuse-3-worker | 3.158.0-r0 | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| npm | hono | < 4.12.7 | 4.12.7 | GHSA-v8w9-8mx6-g223 |
References
- GitHub Security Advisory (GHSA-v8w9-8mx6-g223) vendor-advisory
- VulnCheck Advisory: Hono - Prototype Pollution via __proto__ Key in parseBody with dot Option third-party-advisory