CVE-2026-111757 is a medium-severity (CVSS 5.3) CWE-174 vulnerability in hono. A fix is available for hono — see the affected versions and patch details below.
Hono: `serveStatic` decodes the request path a second time, leading to bypass of middleware on static paths
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-111757.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2026-111757 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 394,803 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
hononpmDescription
Summary
serveStatic decodes the request path a second time after Hono has already decoded it for routing. A crafted request can be routed as one path and served as another, so middleware mounted on a static prefix does not run for a file under that prefix.
Details
Hono decodes the request path once before routing. serveStatic decoded it again before resolving the file. With a malformed percent-encoded sequence, the first decode leaves part of the path encoded, the router matches the encoded form, and the second decode resolves the real directory. The file is still resolved inside the configured root; this is not a traversal outside it.
Impact
An unauthenticated attacker may reach static files without the middleware on their prefix running, for example an authentication check. This affects applications that mount middleware on part of the directory served by serveStatic. Applications that serve only public files are not affected.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | hono | ≥ 4.12.4&&< 4.13.11 | 4.13.11npm install hono@4.13.11 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for hono, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update hono to 4.13.11 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-111757 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat Hardened Images | grafana13-1-main-13.1.7-0.2.hum1 | RHSA-2026:84423 |
| Red Hat Hardened Images | grafana12-4-main-12.4.13-0.1.hum1 | RHSA-2026:85295 |
| Red Hat Hardened Images | grafana13-2-main-13.2.4-0.1.hum1 | RHSA-2026:85544 |
Frequently Asked Questions
Is CVE-2026-111757 in your dependencies?
Find it across npm, including transitive dependencies.