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CVE-2021-39275

ap_escape_quotes buffer overflow

Published: Sep 16, 2021Updated: May 1, 2025 Sources: CVE List NVD BDU csafCWE-787
NVD MITRE
9.8CVSSCRITICAL
EPSS Score
36.3%
Top 1.7%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Am I actually vulnerable?1 Nuclei template available — see how to check your systems. How to verify

Description

ap_escape_quotes() may write beyond the end of a buffer when given malicious input. No included modules pass untrusted data to these functions, but third-party / external modules may. This issue affects Apache HTTP Server 2.4.48 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

Apache HTTP ServerApache Software Foundation
On-premWeb App
Networking Infrastructure / load-balancer-proxy
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
cloud backupnetappHardware Firmware
apache software foundationoss-projectUSWeb & CMS Pluginsaka apache foundation
apacheoss-projectUSWeb & CMS Pluginsaka apache http server, apache httpd
fedoraprojectoss-projectUSOperating Systemsaka fedora project
debianoss-projectGBOperating Systemsaka debian gnu/linux
netappcommercialUSHardware Firmware
and 17 more affected products View all →

Attack Graph

Products CVE Techniques Tactics

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Exploitability

Official Patch Available

MITRE ATT&CK

2 techniques
Initial Access
Privilege Escalation
View detailed technique mapping

References

https://httpd.apache.org/security/vulnerabilities_24.html
httpd.apache.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SPBR6WUYBJNACHKE65SPL7TJOHX7RHWD/
lists.fedoraproject.org
https://lists.apache.org/thread.html/r82838efc5fa6fc4c73986399c9b71573589f78b31846aff5bd9b1697%40%3Cusers.httpd.apache.org%3E
lists.apache.org
and 35 more references View all →

Timeline

Published
Sep 16, 2021
Last Updated
May 1, 2025

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