CVE-2026-48043 is a medium-severity uncontrolled resource consumption vulnerability in io.netty:netty-codec-http2 (maven), affecting versions <= 4.1.134.Final. It is fixed in 4.1.135.Final, 4.2.15.Final.
Impact The DelegatingDecompressorFrameListener class orchestrates HTTP/2 decompression by embedding a per-stream EmbeddedChannel that runs the appropriate decompression codec (gzip, deflate, zstd) and forwards decompressed chunks to a wrapped listener. Each decompressed chunk is a pooled ByteBuf handed to an anonymous ChannelInboundHandlerAdapter tail handler, which becomes the sole owner responsible for releasing it. A remote peer could send frames that would result in the flow-controller throwing and so trigger a resource leak which at the end might take down the whole JVM due OOME.
Crafted input forces the application to consume excessive CPU, memory, or other resources, degrading or denying service. Typical impact: denial of service.
CVE-2026-48043 has a CVSS score of 5.3 (Medium). 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 (4.1.135.Final, 4.2.15.Final). Upgrading removes the vulnerable code path.
maven
io.netty:netty-codec-http2 (<= 4.1.134.Final)io.netty:netty-codec-http2 (>= 4.2.0.Alpha1, <= 4.2.14.Final)io.netty:netty-codec-http2 → 4.1.135.Final (maven)io.netty:netty-codec-http2 → 4.2.15.Final (maven)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-2026-48043 is reachable in your applications. Explore open-source security for your team.
See if CVE-2026-48043 is reachable in your applications. Get a demo
Upgrade the following packages to resolve this vulnerability:
io.netty:netty-codec-http2 to 4.1.135.Final or laterio.netty:netty-codec-http2 to 4.2.15.Final or laterKodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.
CVE-2026-48043 is a medium-severity uncontrolled resource consumption vulnerability in io.netty:netty-codec-http2 (maven), affecting versions <= 4.1.134.Final. It is fixed in 4.1.135.Final, 4.2.15.Final. Crafted input forces the application to consume excessive CPU, memory, or other resources, degrading or denying service.
CVE-2026-48043 has a CVSS score of 5.3 (Medium). 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.
io.netty:netty-codec-http2 (maven) versions <= 4.1.134.Final is affected.
Yes. CVE-2026-48043 is fixed in 4.1.135.Final, 4.2.15.Final. Upgrade to this version or later.
Whether CVE-2026-48043 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
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.
io.netty:netty-codec-http2 to 4.1.135.Final or laterio.netty:netty-codec-http2 to 4.2.15.Final or later