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Vulnerability Intelligence

CVE-2021-44228

CriticalExploitedPublic exploit

Remote code injection in Log4j

Published Dec 10, 2021 · Updated Aug 13, 2026 · Also known as DEBIAN-CVE-2021-44228, DLA-2842-1, DSA-5020-1, GHSA-jfh8-c2jp-5v3q, Log4Shell, Log4Shell RCE, LogShell, TR-21-0987, TR-21-0988, TR-21-0993, TR-21-1003, TR-21-1020, TR-21-1022, TR-21-1037, TR-22-0012, TR-22-0074, TR-22-0133, TR-22-0140, TR-22-0152, TR-22-0248, TR-22-0256, UBUNTU-CVE-2021-44228, USN-5192-1, USN-5192-2, USN-5197-1

Key Facts

Patch immediately
  • CVE-2021-44228 is a critical-severity vulnerability (CVSS 10.0 v3.1) affecting Log4j (Apache), Xcode (Apple), Synchro 4d (Bentley) and 22 more products.
  • It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Dec 6, 2021 and is known to be used in ransomware campaigns. Public exploit code is available.
  • EPSS estimates a 100% probability of exploitation in the next 30 days.
  • Fixed versions are available, including Log4j 2.12.2, Log4j 2.15.0, Log4j 2.3.1.
  • Brandefense priority: patch immediately, because it is listed as exploited in the wild.

CVSS v3.1

10.0

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

EPSS (30-day exploit likelihood)

100%

Higher than 99.9% of all scored CVEs

Exploited in the wild

Yes

4 catalog listings, used by ransomware

Public exploit code

Available

Proof-of-concept or weaponized module

Get the full CVE-2021-44228 brief as a PDF

Every affected product and fixed release, exploitation status and a first 24 hours response checklist, emailed within minutes.

Description

Apache Log4j2 2.0-beta9 through 2.15.0 (excluding security releases 2.12.2, 2.12.3, and 2.3.1) JNDI features used in configuration, log messages, and parameters do not protect against attacker controlled LDAP and other JNDI related endpoints. An attacker who can control log messages or log message parameters can execute arbitrary code loaded from LDAP servers when message lookup substitution is enabled. From log4j 2.15.0, this behavior has been disabled by default. From version 2.16.0 (along with 2.12.2, 2.12.3, and 2.3.1), this functionality has been completely removed. Note that this vulnerability is specific to log4j-core and does not affect log4net, log4cxx, or other Apache Logging Services projects.

Known-Exploited Catalog Listings

CatalogAddedRemediation dueRansomware use
CISA KEVDec 10, 2021Dec 24, 2021Known
Industry KEV feedDec 6, 2021Dec 24, 2021Known
CIRCL KEVDec 10, 2021Dec 24, 2021Known
ENISA EUVDDec 10, 2021n/aNot reported

Required action: For all affected software assets for which updates exist, the only acceptable remediation actions are: 1) Apply updates; OR 2) remove affected assets from agency networks. Temporary mitigations using one of the measures provided at https://www.cisa.gov/uscert/ed-22-02-apache-log4j-recommended-mitigation-measures are only acceptable until updates are available.

Affected Products

541 affected entries in total
ProductAffected versionsFixed in
Log4jApache2.0, 2.0-beta9, 2.0-rc1, 2.0-rc22.3.1
XcodeAppleSee advisory13.3
Synchro 4dBentleySee advisory6.4.3.2
SynchroBentleySee advisory6.2.4.2
Advanced Malware Protection Virtual Private Cloud ApplianceCiscoSee advisory3.5.4
20 more affected products in the full CVE brief

Patched Releases

Log4j

2.12.2, 2.15.0, 2.3.1, 2.13.0-4.3.1, 2.13.0-4.6.1, 2.13.0-lp152.3.3.1, 2.13.0-lp152.3.6.1, 2.13.2-2.1, 2.15.0-1.amzn2022.0.1, 2.16.0-4.10.1, 2.16.0-lp152.3.9.1, 2.17.2-1.amzn2022.0.3

Apache Log4j2

log4j-core*, 2.10.0-2ubuntu0.1, 2.15.0-0.20.04.1, 2.15.0-1, 2.15.0-1~deb10u1, 2.15.0-1~deb11u1, 2.16.0-0.20.04.1, 2.4-2ubuntu0.1~esm1, 2.7-2+deb9u1

Xcode

13.3

arduino

1:1.8.17-1

aws-kinesis-agent

2.0.4-1.amzn2

Synchro

6.2.4.2

Synchro 4d

6.4.3.2

Advanced Malware Protection Virtual Private Cloud Appliance

3.5.4

Automated Subsea Tuning

2.1.0

Broadworks

2021.11_1.162

Business Process Automation

3.0.000.115, 3.1.000.044, 3.2.000.009

Cloud Connect

12.6\(1\)

Cloudcenter

4.10.0.16

Cloudcenter Cost Optimizer

5.5.2

Cloudcenter Suite Admin

5.3.1

Cloudcenter Workload Manager

5.5.2

Common Services Platform Collector

2.10.0.1, 2.9.1.3

Contact Center Domain Manager

12.5\(1\)

Contact Center Management Portal

12.5\(1\)

Crosswork Data Gateway

2.0.2

Crosswork Network Controller

2.0.1

Crosswork Optimization Engine

2.0.1

Crosswork Platform Infrastructure

4.0.1

Crosswork Zero Touch Provisioning

2.0.1

Customer Experience Cloud Agent

1.12.1

Timeline

  1. Added to Industry KEV feed

    Dec 6, 2021

  2. Publicly disclosed

    Dec 10, 2021

  3. Added to CISA KEV

    Dec 10, 2021

  4. Added to CIRCL KEV

    Dec 10, 2021

  5. Added to ENISA EUVD

    Dec 10, 2021

  6. Last updated

    Aug 13, 2026

Weakness Type

  • CWE-20 Improper Input Validation
  • CWE-400 Uncontrolled Resource Consumption
  • CWE-502 Deserialization of Untrusted Data
  • CWE-917 Improper Neutralization of Special Elements used in an Expression Language Statement ('Expression Language Injection')

References

15 more references in the full CVE brief

FAQ

Common Questions.

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