CVE-2026-33814
Description
A flaw was found in the HTTP/2 protocol implementation within the Go standard library (golang.org/x/net and net/http/internal/http2). A remote attacker can exploit this vulnerability by sending a specially crafted HTTP/2 SETTINGS frame with the SETTINGS_MAX_FRAME_SIZE parameter set to zero. This malicious frame causes the transport layer to enter an infinite loop of writing CONTINUATION frames, leading to resource exhaustion and a Denial of Service (DoS) condition.
Statement
This Important denial of service flaw in the Go HTTP/2 protocol implementation allows a remote, unauthenticated attacker to exhaust system resources. By sending a specially crafted HTTP/2 SETTINGS frame with a zero-value SETTINGS_MAX_FRAME_SIZE, the vulnerable Go library enters an infinite loop, impacting the availability of services utilizing HTTP/2.
Mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
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 | 7.5 |
| Attack Vector | Network | Network | Network |
| Attack Complexity | Low | Low | Low |
| Privileges Required | None | None | None |
| User Interaction | None | None | None |
| Scope | Unchanged | Unchanged | Unchanged |
| Confidentiality | None | None | None |
| Integrity Impact | None | None | None |
| Availability Impact | High | High | High |
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
cve.org: 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 (CPU)
Frequently Asked Questions
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