CVE-2026-24472 is a medium-severity (CVSS 5.3) CWE-524 vulnerability in hono. A fix is available for hono — see the affected versions and patch details below.
Hono cache middleware ignores "Cache-Control: private" leading to Web Cache Deception
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-2026-24472.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2026-24472 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,636 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
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
Cache Middleware contains an information disclosure vulnerability caused by improper handling of HTTP cache control directives. The middleware does not respect standard cache control headers such as Cache-Control: private or Cache-Control: no-store, which may result in private or authenticated responses being cached and subsequently exposed to unauthorized users.
Details
The vulnerability exists in the cache decision logic of Cache Middleware. When determining whether a response should be cached, the middleware does not take HTTP cache control semantics into account and may cache responses that are explicitly marked as private by the application. While some runtimes, such as Cloudflare Workers, enforce cache control restrictions at the platform level, other runtimes including Deno, Bun, and Node.js rely on the middleware’s behavior. As a result, applications running on these runtimes may unintentionally cache sensitive responses.
Impact
This issue can lead to Web Cache Deception and information disclosure. If an authenticated user accesses an endpoint that returns user-specific or sensitive data and the response is cached despite being marked as private, subsequent unauthenticated requests may receive the cached response. This may result in the exposure of personally identifiable information or session-related data. The impact is limited to applications that use the hono/cache middleware and rely on it to correctly honor HTTP cache control directives.
Affected Components
- Cache Middleware
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | hono | all versions | 4.11.7npm install hono@4.11.7 |
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 4.11.7 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-24472 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.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-24472 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-24472. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-24472 in your dependencies?
O3 Security finds CVE-2026-24472 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.