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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2021-33193 Detail

Description

A crafted method sent through HTTP/2 will bypass validation and be forwarded by mod_proxy, which can lead to request splitting or cache poisoning. This issue affects Apache HTTP Server 2.4.17 to 2.4.48.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/apache/httpd/commit/ecebcc035ccd8d0e2984fe41420d9e944f456b3c.patch Apache Software Foundation, CVE Patch 
https://lists.apache.org/thread.html/re4162adc051c1a0a79e7a24093f3776373e8733abaff57253fef341d%40%3Ccvs.httpd.apache.org%3E Apache Software Foundation, CVE Patch 
https://lists.apache.org/thread.html/ree7519d71415ecdd170ff1889cab552d71758d2ba2904a17ded21a70%40%3Ccvs.httpd.apache.org%3E Apache Software Foundation, CVE Patch 
https://lists.debian.org/debian-lts-announce/2023/03/msg00002.html Apache Software Foundation, CVE Mailing List  Third Party Advisory 
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/DSM6UWQICBJ2TU727RENU3HBKEAFLT6T/ Apache Software Foundation, CVE Third Party Advisory 
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/EUVJVRJRBW5QVX4OY3NOHZDQ3B3YOTSG/ Apache Software Foundation, CVE Third Party Advisory 
https://portswigger.net/research/http2 Apache Software Foundation, CVE Exploit  Third Party Advisory 
https://security.gentoo.org/glsa/202208-20 Apache Software Foundation, CVE Third Party Advisory 
https://security.netapp.com/advisory/ntap-20210917-0004/ Apache Software Foundation, CVE Third Party Advisory 
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-apache-httpd-2.4.49-VWL69sWQ Apache Software Foundation, CVE Third Party Advisory 
https://www.oracle.com/security-alerts/cpuapr2022.html Apache Software Foundation, CVE Patch  Third Party Advisory 
https://www.oracle.com/security-alerts/cpujan2022.html Apache Software Foundation, CVE Patch  Third Party Advisory 
https://www.tenable.com/security/tns-2021-17 Apache Software Foundation, CVE Third Party Advisory 

Weakness Enumeration

CWE-ID CWE Name Source
NVD-CWE-Other Other cwe source acceptance level NIST  

Known Affected Software Configurations Switch to CPE 2.2

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Change History

22 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2021-33193
NVD Published Date:
08/16/2021
NVD Last Modified:
05/01/2025
Source:
Apache Software Foundation