🛡️ CVE-2021-33193 — apache
Description
Request splitting via HTTP/2 method injection and mod_proxy
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.
Affected software
CVE-2021-33193 is recorded against 1 package.
- apache
Timeline and source
Published on 6 March 2024 and last revised on 20 May 2025. No public exploit is currently recorded for this entry. Record sourced from OSV.
References
github.com (Web)
lists.apache.org (Web)
lists.apache.org (Web)
lists.debian.org (Web)
lists.fedoraproject.org (Web)
lists.fedoraproject.org (Web)
portswigger.net (Web)
security.gentoo.org (Web)
security.netapp.com (Web)
tools.cisco.com (Web)
www.oracle.com (Web)
www.oracle.com (Web)
www.tenable.com (Web)
nvd.nist.gov (Web)
CVE-2021-33193 on other distributions
Each distribution ships its own build and its own fixed version. Pick the one you run:
Details
Affected Packages
| Software | From version | Fixed in |
|---|---|---|
| apache | — | — |
References
Similar Threats
- Critical CVE-2020-11984
- Medium CVE-2020-11985
- High CVE-2020-11993
- Medium CVE-2020-13938
- High CVE-2020-13950
More CVE 2021 advisories
Browse all of CVE 2021 in the advisory index.
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