7.5
High
io.netty:netty-codec-redis

CVE-2026-50011

CVE-2026-50011 is a high-severity uncontrolled resource consumption vulnerability in io.netty:netty-codec-redis (maven), affecting versions >= 4.2.0.Final, <= 4.2.14.Final. It is fixed in 4.2.15.Final, 4.1.135.Final.

Key facts
CVSS score
7.5
High
Attack vector
Network
Issuing authority
GitHub Advisory Database
Affected package
io.netty:netty-codec-redis
Fixed in
4.2.15.Final, 4.1.135.Final
Disclosed
2026

Summary

Summary RedisArrayAggregator pre-allocates ArrayList with initial capacity equal to the RESP array element count declared in an array header. That count is taken from the wire before the corresponding child messages exist. A small malicious header can claim a huge initial capacity. Details The aggregator starts a new aggregation level when it receives an ArrayHeaderRedisMessage. For positive lengths it pushes AggregateState, whose constructor runs new ArrayList<>(length). No configurable maximum is applied in this handler, and the peer does not need to supply the array elements for the backing array allocation to occur. In the same pipeline, RedisDecoder enforces RedisConstants.REDISMESSAGEMAX_LENGTH for bulk string lengths but does not apply that cap to array header lengths. Declared array sizes can therefore be extremely large while still passing decoding, and the aggregator immediately attempts Object[] reservation. io.netty.handler.codec.redis.RedisDecoder#decodeLength io.netty.handler.codec.redis.RedisArrayAggregator#decodeRedisArrayHeader Impact Availability / resource exhaustion via unbounded pre-allocation from untrusted RESP array headers.

Impact

What is uncontrolled resource consumption?

Crafted input forces the application to consume excessive CPU, memory, or other resources, degrading or denying service. Typical impact: denial of service.

Severity and exposure

CVE-2026-50011 has a CVSS score of 7.5 (High). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment.

A fixed version is available (4.2.15.Final, 4.1.135.Final). Upgrading removes the vulnerable code path.

Affected versions

maven

  • io.netty:netty-codec-redis (>= 4.2.0.Final, <= 4.2.14.Final)
  • io.netty:netty-codec-redis (<= 4.1.134.Final)

Security releases

  • io.netty:netty-codec-redis → 4.2.15.Final (maven)
  • io.netty:netty-codec-redis → 4.1.135.Final (maven)
Kodem intelligence

Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.

Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter instead of chasing every advisory.

Kodem's runtime-powered SCA identifies whether CVE-2026-50011 is reachable in your applications. Explore open-source security for your team.

See if CVE-2026-50011 is reachable in your applications. Get a demo

Remediation advice

Upgrade the following packages to resolve this vulnerability:

  • Upgrade io.netty:netty-codec-redis to 4.2.15.Final or later
  • Upgrade io.netty:netty-codec-redis to 4.1.135.Final or later

Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.

Frequently asked questions about CVE-2026-50011

What is CVE-2026-50011?

CVE-2026-50011 is a high-severity uncontrolled resource consumption vulnerability in io.netty:netty-codec-redis (maven), affecting versions >= 4.2.0.Final, <= 4.2.14.Final. It is fixed in 4.2.15.Final, 4.1.135.Final. Crafted input forces the application to consume excessive CPU, memory, or other resources, degrading or denying service.

How severe is CVE-2026-50011?

CVE-2026-50011 has a CVSS score of 7.5 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.

Which versions of io.netty:netty-codec-redis are affected by CVE-2026-50011?

io.netty:netty-codec-redis (maven) versions >= 4.2.0.Final, <= 4.2.14.Final is affected.

Is there a fix for CVE-2026-50011?

Yes. CVE-2026-50011 is fixed in 4.2.15.Final, 4.1.135.Final. Upgrade to this version or later.

Is CVE-2026-50011 exploitable, and should I be worried?

Whether CVE-2026-50011 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo

What actually determines whether CVE-2026-50011 is exploitable, and how bad it is?

Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.

How do I fix CVE-2026-50011?
  • Upgrade io.netty:netty-codec-redis to 4.2.15.Final or later
  • Upgrade io.netty:netty-codec-redis to 4.1.135.Final or later

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