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CVE-2021-44224

Possible NULL dereference or SSRF in forward proxy configurations in Apache HTTP Server 2.4.51 and earlier

Published: Dec 20, 2021Updated: Nov 21, 2024 Sources: CVE List NVD BDUCWE-476
8.2HIGH
NVD MITRE
EPSS Score
82.3%
Top 0.4%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
Nuclei · OpenVAS

Description

A crafted URI sent to httpd configured as a forward proxy (ProxyRequests on) can cause a crash (NULL pointer dereference) or, for configurations mixing forward and reverse proxy declarations, can allow for requests to be directed to a declared Unix Domain Socket endpoint (Server Side Request Forgery). This issue affects Apache HTTP Server 2.4.7 up to 2.4.51 (included).

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:NI:LA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:LIntegrity
Low
A:HAvailability
High
Open in CVSS calculator →

Weaknesses

CWE-476

Affected Products

oracle
commercial·USaka oracle corp.
communications element managerOn-prem
Communications
communications operations monitorOn-premWeb App
Databases / db-tooling
communications session report managerOn-prem
Communications
communications session route managerOn-prem
Communications / messaging-chat
http serverOn-premWeb App
Web & CMS Plugins
instantis enterprisetrackOn-premWeb App
Enterprise Software / itsm-monitoring
ООО «РусБИТех-Астра»
commercial·RUaka rusbitech-astra
Astra Linux Special EditionOn-premOS
Operating Systems / linux-distro
Astra Linux Common EditionOn-premOS
Operating Systems / linux-distro
Astra Linux Special Edition для «Эльбрус»On-premOS
Operating Systems / linux-distro
АО «НТЦ ИТ РОСА»
commercial·RU
ROSA VirtualizationOn-prem
Operating Systems / linux-distro
ROSA Virtualization 3.0On-prem
Operating Systems / linux-distro
Apache Software Foundation
oss-project·USaka apache foundation
Apache HTTP ServerOn-premWeb App
Networking Infrastructure / load-balancer-proxy
apache
oss-project·USaka apache httpd, apache http server
http serverOn-premWeb App
Networking Infrastructure / load-balancer-proxy
fedoraproject
oss-project·USaka fedora project
fedoraOn-premOS
Operating Systems / linux-distro
and 10 more affected products View all →

Exploitability

Official Patch Available
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Attack Graph

Products CVE Techniques Tactics

Click technique nodes for MITRE ATT&CK details · drag to pan · Ctrl/⌘ + scroll to zoom, or go fullscreen.

MITRE ATT&CK

2 techniques
Impact
Initial Access
View detailed technique mapping

References

http://httpd.apache.org/security/vulnerabilities_24.html
httpd.apache.org
http://www.openwall.com/lists/oss-security/2021/12/20/3
openwall.com
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BFSWOH4X77CV7AH7C4RMHUBDWKQDL4YH/
lists.fedoraproject.org
and 38 more references View all →

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