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CVE-2021-45105

Apache Log4j2 does not always protect from infinite recursion in lookup evaluation

Published: Dec 18, 2021Updated: May 29, 2026 Sources: CVE List NVD GHSA BDUCWE-20
5.9MEDIUM
NVD MITRE
EPSS Score
100.0%
Top 0.0%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
OpenVAS

Description

Apache Log4j2 versions 2.0-alpha1 through 2.16.0 (excluding 2.12.3 and 2.3.1) did not protect from uncontrolled recursion from self-referential lookups. This allows an attacker with control over Thread Context Map data to cause a denial of service when a crafted string is interpreted. This issue was fixed in Log4j 2.17.0, 2.12.3, and 2.3.1.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:HPR:NUI:NS:UC:NI:NA:H
Exploitability
AV:NAttack Vector
Network
AC:HAttack Complexity
High
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:NIntegrity
None
A:HAvailability
High
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Weaknesses

CWE-20CWE-674

Affected Products

oracle
commercial·USaka oracle corp.
agile engineering data managementOn-premWeb App
Enterprise Software / erp
agile plmOn-premDatabase
Databases / data-warehouse-analytics
agile plm mcad connectorOn-prem
Enterprise Software / erp
autovue for agile product lifecycle managementOn-premDesktop App
Enterprise Software / itsm-monitoring
banking deposits and lines of credit servicingOn-prem
Enterprise Software / hr-finance
banking enterprise default managementOn-premDatabase
Databases / relational
banking loans servicingOn-prem
Enterprise Software / hr-finance
banking party managementOn-premWeb App
Enterprise Software / itsm-monitoring
Red Hat Inc.
commercial·USaka red hat
OpenShift Container PlatformOn-prem
Operating Systems / linux-distro
Jboss FuseOn-prem
Operating Systems / linux-distro
JBoss Enterprise Application PlatformOn-prem
Operating Systems / linux-distro
OpenShift Application RuntimesOn-prem
Operating Systems / linux-distro
Red Hat Single Sign-OnOn-prem
Operating Systems / linux-distro
Red Hat Descision ManagerOn-prem
Operating Systems / linux-distro
JBoss A-MQ StreamingOn-prem
Operating Systems / linux-distro
CodeReady StudioOn-prem
Operating Systems / linux-distro
sonicwall
commercial·US
email security
Networking Infrastructure
network security manager
Networking Infrastructure
web application firewall
Networking Infrastructure
6bk1602-0aa12-0tp0 firmware
Networking Infrastructure
6bk1602-0aa22-0tp0 firmware
Networking Infrastructure
6bk1602-0aa32-0tp0 firmware
Networking Infrastructure
6bk1602-0aa42-0tp0 firmware
Networking Infrastructure
6bk1602-0aa52-0tp0 firmware
Networking Infrastructure
NetApp Inc.
commercial·USaka netapp
Cloud Manager
Hardware Firmware
ONTAP Tools for VMware vSphere
Hardware Firmware
Snap Creator Framework
Hardware Firmware
Apache Software Foundation
oss-project·USaka apache foundation
Log4jLibraryLibrary
OSS Libraries / generic-library
Apache Log4j2On-premLibrary
OSS Libraries / web-framework
Maven
package-ecosystem
org.apache.logging.log4j:log4j-core
OSS Libraries
org.ops4j.pax.logging:pax-logging-log4j2
OSS Libraries
and 110 more affected products View all →

Exploitability

Official Patch Available
Workaround 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

https://access.redhat.com/security/cve/CVE-2021-45105
access.redhat.com
https://logging.apache.org/log4j/2.x/security.html
logging.apache.org
https://redos.red-soft.ru/support/secure/
redos.red-soft.ru
and 29 more references View all →

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