CVE-2026-48040 — netty-incubator-codec-oht…
Fix: netty/netty-incubator-codec-ohttp@7ad38d5CVE-2026-48040 is a Out-of-bounds Read vulnerability in io.netty.incubator:netty-incubator-codec-ohttp-hpke-native-boringssl. A fix is available for io.netty.incubator:netty-incubator-codec-ohttp-hpke-native-boringssl — see the affected versions and patch details below.
netty-incubator-codec-ohttp's Incorrect Native Pointer Derivation in Pooled Direct ByteBuf Fallback Leads to Out-of-Bounds Native Memory Access
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.
- A successful exploit gives an attacker total control of the affected component, not partial access.
- 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-2026-48040.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
Real-World Exposure
io.netty.incubator:netty-incubator-codec-ohttp-hpke-native-boringsslReal-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. The library implements Oblivious HTTP (RFC 9458) using BoringSSL's HPKE C library via JNI. When deriving native memory addresses for cryptographic operations versions prior to 0.0.22.Final provide a fallback path for direct ByteBufs that do not expose their memory address through hasMemoryAddress(). This fallback occurs when sun.misc.Unsafe is unavailable to Netty — for example, when the JVM is started with -Dio.netty.noUnsafe=true, when a SecurityManager restricts Unsafe access, or when running on non-HotSpot JVMs. In these configurations, Netty's default PooledByteBufAllocator returns PooledDirectByteBuf instances for which hasMemoryAddress() returns false. Under the enabling JVM configuration, an unauthenticated network attacker can cause the OHTTP gateway to corrupt memory belonging to other concurrent connections and disclose the contents of adjacent pooled direct buffers by triggering cryptographic operations with crafted OHTTP requests. The corruption occurs regardless of whether the AEAD tag verification succeeds, as BoringSSL zeroizes the output buffer on failure. The information disclosure path provides the attacker with the encryption key needed to extract the leaked data. This violates the confidentiality and integrity of all connections sharing the same Netty buffer arena. Version 0.0.22.Final fixes the issue.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | io.netty.incubator:netty-incubator-codec-ohttp-hpke-native-boringssl | all versions | 0.0.22.Finalio.netty.incubator:netty-incubator-codec-ohttp-hpke-native-boringssl:0.0.22.Final |
Affected Products
netty-incubator-codec-ohttpnettyDetection & 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-hpke-native-boringssl, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update io.netty.incubator:netty-incubator-codec-ohttp-hpke-native-boringssl to 0.0.22.Final or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-48040 is resolved across your whole dependency graph.
Workarounds
Stop feeding it untrusted input: reject or quarantine files and payloads from unverified sources until you can upgrade, restrict accepted formats to the ones you actually need, and run the parsing or decoding step in a least-privileged sandbox or short-lived worker so a crash or corrupted read cannot reach the rest of the process.
Frequently Asked Questions
Is CVE-2026-48040 in your dependencies?
Find it across Maven, including transitive dependencies.