CVE-2026-56745
Description
A flaw was found in Netty. A remote attacker can exploit a vulnerability in the SpdyHttpDecoder handler of Netty's SPDY-to-HTTP codec. When processing a client-initiated SYN_STREAM frame, the decoder fails to release allocated memory if the stream is reset or content limits are exceeded. This oversight leads to native memory exhaustion, which can result in a Denial of Service (DoS) for the affected system.
Statement
This is an Important denial of service vulnerability in Netty's SPDY-to-HTTP codec, affecting Red Hat products that utilize vulnerable versions of Netty. A remote, unauthenticated attacker can exploit a memory leak in the SpdyHttpDecoder by sending specially crafted SYN_STREAM frames, leading to native memory exhaustion and a denial of service for the affected system.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 7.5 | 7.5 | N/A |
| Attack Vector | Network | Network | N/A |
| Attack Complexity | Low | Low | N/A |
| Privileges Required | None | None | N/A |
| User Interaction | None | None | N/A |
| Scope | Unchanged | Unchanged | N/A |
| Confidentiality | None | None | N/A |
| Integrity Impact | None | None | N/A |
| Availability Impact | High | High | N/A |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Resource Consumption (Other); DoS: Resource Consumption (Memory); DoS: Resource Consumption (CPU)
An attacker that can influence the allocation of resources that are not properly released could deplete the available resource pool and prevent all other processes from accessing the same type of resource. Frequently-affected resources include memory, CPU, disk space, power or battery, etc.
Frequently Asked Questions
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