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CVE-2021-44790

Possible buffer overflow when parsing multipart content in mod_lua of Apache HTTP Server 2.4.51 and earlier

Published: Dec 20, 2021Updated: May 1, 2025 Sources: CVE List NVD BDU csafCWE-787
NVD MITRE
9.8CVSSCRITICAL
EPSS Score
97.1%
Top 0.1%
CISA KEV
Not in KEV
Exploits
1 Known
Remediation
Patch Available
Am I actually vulnerable?1 Nuclei template available — see how to check your systems. How to verify

Description

A carefully crafted request body can cause a buffer overflow in the mod_lua multipart parser (r:parsebody() called from Lua scripts). The Apache httpd team is not aware of an exploit for the vulnerabilty though it might be possible to craft one. This issue affects Apache HTTP Server 2.4.51 and earlier.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:HI:HA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:HAvailability
High
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Weaknesses

CWE-787

Affected Products

http serverapache
On-premWeb App
Networking Infrastructure / load-balancer-proxy
fedorafedoraproject
On-premOS
Operating Systems / linux-distro
debian linuxdebian
On-premOS
Operating Systems / linux-distro
tenable.sctenable
cloud backupnetappHardware Firmware
apacheoss-projectUSWeb & CMS Pluginsaka apache http server, apache httpd
fedoraprojectoss-projectUSOperating Systemsaka fedora project
debianoss-projectGBOperating Systemsaka debian gnu/linux
netappcommercialUSHardware Firmware
and 22 more affected products View all →

Attack Graph

Products CVE Techniques Tactics

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Exploitability

1 exploit source identified

Exploit details including PoC links, Metasploit modules, and scanner templates are available after registration.

View exploit details
Official Patch Available

MITRE ATT&CK

2 techniques
Initial Access
Privilege Escalation
View detailed technique mapping

References

http://httpd.apache.org/security/vulnerabilities_24.html
httpd.apache.org
http://packetstormsecurity.com/files/171631/Apache-2.4.x-Buffer-Overflow.html
packetstormsecurity.com
http://seclists.org/fulldisclosure/2022/May/33
seclists.org
and 55 more references View all →

Timeline

Published
Dec 20, 2021
Last Updated
May 1, 2025

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