BoringSSLAEADContext in Netty Repeats NoncesGHSA-g762-h86w-8749
MEDIUMGHSA-g762-h86w-8749 is a medium-severity (CVSS 5.9) CWE-190 vulnerability in io.netty.incubator:netty-incubator-codec-ohttp. 1 public exploit or proof-of-concept reference is indexed, so weaponization risk is real. A fix is available for io.netty.incubator:netty-incubator-codec-ohttp — see the affected versions and patch details below.
Exploitation Status
No confirmed exploitation observed yet
- 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 GHSA-g762-h86w-8749.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
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
Summary
BoringSSLAEADContext keeps track of how many OHTTP responses have been sent and uses this sequence number to calculate the appropriate nonce to use with the encryption algorithm. Unfortunately, two separate errors combine which would allow an attacker to cause the sequence number to overflow and thus the nonce to repeat.
Details
- There is no overflow detection or enforcement of the maximum sequence value. (This is a missed requirement from the draft Chunked Oblivious OHTTP RFC and so should be inherited from the HPKE RFC 9180, Section 5.2).
- The sequence number (seq) is stored as 32-bit int which is relatively easy to overflow.
Impact
If the BoringSSLAEADContext is used to encrypt more than 2^32 messages then the AES-GCM nonce will repeat. Repeating a nonce with AES-GCM results in both confidentiality and integrity compromise of data encrypted with the associated key.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | io.netty.incubator:netty-incubator-codec-ohttp | ≥ 0.0.3.Final&&< 0.0.11.Final | 0.0.11.Finalio.netty.incubator:netty-incubator-codec-ohttp:0.0.11.Final |
Affected Products
netty-incubator-codec-ohttpnettyResearch use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
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, 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 to 0.0.11.Final or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-g762-h86w-8749 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 GHSA-g762-h86w-8749 in your dependencies?
Find it across Maven, including transitive dependencies.