CVE-2020-11984
Description
A flaw was found in Apache httpd in versions 2.4.32 to 2.4.46. The uwsgi protocol does not serialize more than 16K of HTTP header leading to resource exhaustion and denial of service. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
Statement
Red Hat Enterprise Linux 5, 6, and 7 do not ship the vulnerable version of httpd and, thus, are not affected.
Mitigation
This flaw only affects specific httpd configurations which use the uwsgi protocol. It does not manifest itself when uwsgi protocol is not used. Commenting out "LoadModule proxy_uwsgi_module modules/mod_proxy_uwsgi.so" in /etc/httpd/conf.modules.d/00-proxy.conf will disable the loading of the vulnerable module.
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 | 9.8 | 9.8 | 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 | High | High | N/A |
| Integrity Impact | High | High | 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:H/I:H/A:H
NVD: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/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.
Acknowledgements
Red Hat would like to thank the Apache project for reporting this issue.
Frequently Asked Questions
Not sure what something means? Check out our Security Glossary.
Want to get errata notifications? Sign up here.
