HTTP Request Smuggling Affecting langfuse-4-worker package, versions <4.30.0-r0
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-MINIMOSLATEST-LANGFUSE4WORKER-19664409
- published10 Sept 2026
- disclosed1 Sept 2026
Introduced: 1 Sep 2026
NewCVE-2026-84363 (opens in a new tab)How to fix?
Upgrade Minimos:latest langfuse-4-worker to version 4.30.0-r0 or higher.
NVD Description
Note: Versions mentioned in the description apply only to the upstream langfuse-4-worker package and not the langfuse-4-worker package as distributed by Minimos.
See How to fix? for Minimos:latest relevant fixed versions and status.
Hono is a Web application framework that provides support for any JavaScript runtime. Prior to 4.13.5, Hono's query helpers treat a question mark after a literal hash fragment as the start of a query string, so the application can read request parameters that browsers, new URL(), reverse proxies, filtering rules, parameter allow and deny lists, access logging, request validation, and other middleware do not observe. The Cache Middleware removes the fragment when building its cache key, allowing a response influenced by parameters inside the fragment to be stored under a key that omits those parameters and later served to other users. This can bypass filtering and auditing, poison cached responses, and enable stored cross-site scripting when an affected parameter is reflected into cached HTML without escaping. Exploitation requires a runtime and intermediary path that passes a literal hash character through to the request URL; Cloudflare Workers and intermediaries that strip fragments are not affected. This issue is fixed in version 4.13.5.
References
- https://www.cve.org/CVERecord?id=CVE-2026-84363
- https://github.com/advisories/GHSA-crvj-82cr-hjcx
- https://osv.dev/vulnerability/MINI-3hcc-xhhv-r5fx
- https://osv.dev/vulnerability/CVE-2026-84363
- https://github.com/honojs/hono/commit/9c28d724c5a7fb086ebaa812fdc1ad6e957c63bc
- https://github.com/honojs/hono/releases/tag/v4.13.5
- https://github.com/honojs/hono/security/advisories/GHSA-crvj-82cr-hjcx