CVE-2021-33193

Home/CVE/A crafted method sent through HTTP/2 will bypass validation and be forwarded by mod_proxy, which can lead to request spl

CVE

A crafted method sent through HTTP/2 will bypass validation and be forwarded by mod_proxy, which can lead to request spl

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.

HIGH · CVSS 7.5 EPSS 0.00609

Act now

Public exploit or PoC is available
CVSS base score ≥ 7.0

Sigma rules0 YARA rules0

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Affected Products & Versions

debian linuxall versions
apache http server>= 2.4.17 and < 2.4.49
fedoraproject fedoraall versions
tenable tenable.sc<= 5.19.1
oracle secure backup< 18.1.0.1.0
oracle zfs storage appliance kitall versions

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Public Exploits & PoCs

pocportswigger.net · http2portswigger.net

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Scoring & Timeline

7.5

HIGH · CVSS v3.1 · security@apache.org

View on NVD

Attack Vector

Network Adjacent Local Physical

Attack Complexity

Low High

Privileges Required

None Low High

User Interaction

None Required

Scope

Unchanged Changed

Confidentiality

None Low High

Integrity

None Low High

Availability

None Low High

Published to NVD16 Aug 2021 · 08:15 AM

CVSS VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

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Vendor Advisories

rhsaRHSA-2022:6753Moderate
rhsaRHSA-2022:7144Moderate
rhsaRHSA-2022:1915Moderate
rhsaRHSA-2022:7143Moderate
cisco-csafcisco-sa-apache-httpd-2.4.49-VWL69sWQ
Show all 13 vendor advisoriessuse-csafSUSE-SU-2021:3335-1
usnUSN-5090-1
suse-csafopenSUSE-SU-2021:1234-1
suse-csafopenSUSE-SU-2021:2954-1
suse-csafSUSE-SU-2021:2954-1
suse-csafSUSE-SU-2021:2918-1
msrcCVE-2021-33193
oracle-cpuoracle-cpu-Instantis-EnterpriseTrack-10563--CVE-2021-33193

🔗

References & Sources

Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.

https://github.com/apache/httpd/commit/ecebcc035ccd8d0e2984fe41420d9e944f456b3c.patchPatch

https://lists.apache.org/thread.html/re4162adc051c1a0a79e7a24093f3776373e8733abaff57253fef341d%40%3Ccvs.httpd.apache.org%3EPatch

https://lists.apache.org/thread.html/ree7519d71415ecdd170ff1889cab552d71758d2ba2904a17ded21a70%40%3Ccvs.httpd.apache.org%3EPatch

https://lists.debian.org/debian-lts-announce/2023/03/msg00002.htmlMailing ListThird Party Advisory

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/DSM6UWQICBJ2TU727RENU3HBKEAFLT6T/Third Party Advisory

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/EUVJVRJRBW5QVX4OY3NOHZDQ3B3YOTSG/Third Party Advisory

Show all 12 references

https://security.gentoo.org/glsa/202208-20Third Party Advisory

https://security.netapp.com/advisory/ntap-20210917-0004/Third Party Advisory

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-apache-httpd-2.4.49-VWL69sWQThird Party Advisory

https://www.oracle.com/security-alerts/cpuapr2022.htmlPatchThird Party Advisory

https://www.oracle.com/security-alerts/cpujan2022.htmlPatchThird Party Advisory

https://www.tenable.com/security/tns-2021-17Third Party Advisory

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