GHSA-3244-j874-rhc2
HIGHGHSA-3244-j874-rhc2 is a high-severity (CVSS 7.5) Uncontrolled Resource Consumption vulnerability in io.netty:netty-codec-redis. O3 Security confirms whether GHSA-3244-j874-rhc2 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Netty: Memory Exhaustion in RedisArrayAggregator due to Deeply Nested Arrays
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 GHSA-3244-j874-rhc2.
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
GHSA-3244-j874-rhc2 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 0 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
io.netty:netty-codec-redis☕io.netty:netty-codec-redisReal-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
An attacker can cause DoS by sending a crafted Redis payload with deeply nested arrays. This forces the server to allocate a massive number of state objects and collections, leading to memory exhaustion and an OutOfMemoryError.
Details
io.netty.handler.codec.redis.RedisArrayAggregator aggregates RedisMessage parts into ArrayRedisMessage. It uses a Deque<AggregateState> to keep track of nested arrays. However, it does not limit the maximum depth of nested arrays. When an attacker sends a continuous stream of nested array headers (e.g., *1\r\n*1\r\n*1\r\n...), RedisArrayAggregator pushes a new AggregateState onto the stack and allocates a new ArrayList for each header. Because there is no depth limit, an attacker can send millions of such headers. This consumes a massive amount of heap memory for the AggregateState instances and their backing ArrayLists, eventually resulting in an OutOfMemoryError.
Impact
Denial of Service due to memory exhaustion. Any application using Netty's RedisArrayAggregator to handle untrusted Redis traffic is vulnerable.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | io.netty:netty-codec-redis | ≥ 4.2.0.Final&&< 4.2.15.Final | 4.2.15.Final |
| ☕Maven | io.netty:netty-codec-redis | all versions | 4.1.135.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:netty-codec-redis. 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:netty-codec-redis to 4.2.15.Final or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-3244-j874-rhc2 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 GHSA-3244-j874-rhc2 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 GHSA-3244-j874-rhc2. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
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.
This is an Important denial of service vulnerability in netty-codec-redis, affecting Red Hat products that process Redis payloads. A remote attacker can exhaust server memory by sending a crafted Redis payload with deeply nested arrays, leading to an OutOfMemoryError and rendering the service unresponsive. This impact…
Frequently Asked Questions
Is GHSA-3244-j874-rhc2 in your dependencies?
O3 detects GHSA-3244-j874-rhc2 across Maven dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.