CVE-2026-54399
Description
A flaw was found in Apache HttpComponents Core. This uncontrolled resource consumption vulnerability in the HTTP/1.1 message parser allows a remote attacker to cause a denial of service through memory exhaustion. This can be triggered by sending messages with an excessive number of headers or excessive header length.
Statement
Important: This flaw in Apache HttpComponents Core allows a remote attacker to cause a denial of service by sending HTTP/1.1 messages with an excessive number or length of headers. This can lead to memory exhaustion in applications using the affected HTTP/1.1 message parser, impacting service availability.
Mitigation
To mitigate this issue, configure an upstream proxy or web application firewall (WAF) to enforce limits on the number and length of HTTP headers. This prevents malformed requests from reaching and exhausting the vulnerable Apache HttpComponents Core component. Consult your proxy or WAF documentation for specific configuration. A service restart may be required for changes to take effect.
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 | N/A | 7.5 |
| Attack Vector | Network | N/A | Network |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | None | N/A | None |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | None | N/A | None |
| Integrity Impact | None | N/A | None |
| Availability Impact | High | N/A | High |
Vector
Red Hat: 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); DoS: Resource Consumption (Memory); DoS: Resource Consumption (Other)
When allocating resources without limits, an attacker could prevent other systems, applications, or processes from accessing the same type of resource. It can be easy for an attacker to consume many resources by rapidly making many requests or causing larger resources to be used than is needed.
Frequently Asked Questions
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