CVE-2026-41207
Fix: netty/netty-incubator-codec-ohttp@3d3b4e5CVE-2026-41207 is a Insufficient Random Values vulnerability in io.netty.incubator:netty-incubator-codec-ohttp. O3 Security confirms whether CVE-2026-41207 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
netty-incubator-codec-ohttp's HPKEContext operations may produce empty byte[] on failures
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-2026-41207.
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.
Real-World Exposure
io.netty.incubator:netty-incubator-codec-ohttpReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.
Description
The netty incubator codec.bhttp is a java language binary http parser. Prior to version 0.0.21.Final, HKDF_expand returns non-NULL on failure. The byte[] is filled with zeros and has no way to distinguish success from failure. Since this output is used as HKDF key material for the response AEAD, a failure silently produces an all-zero key. When EVP_HPKE_CTX_export fails it also returns an empty byte[] array filled with zeros. This byte[] feeds directly into OHttpCrypto.createResponseAEAD(...). A silent all-zero export secret would produce a deterministic, attacker-predictable AEAD key. Version 0.0.21.Final patches the issue.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | io.netty.incubator:netty-incubator-codec-ohttp | all versions | 0.0.21.Final |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for io.netty.incubator:netty-incubator-codec-ohttp. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update io.netty.incubator:netty-incubator-codec-ohttp to 0.0.21.Final or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-41207 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 pinpoints whether CVE-2026-41207 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-41207. 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-2026-41207 in your dependencies?
O3 detects CVE-2026-41207 across Maven dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.