CVE-2021-45105
5.9 · MEDIUMOverview
CVE-2021-45105 is a medium-severity vulnerability affecting apache log4j. It was published on December 18, 2021 and has a CVSS 3.1 base score of 5.9 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 5.9, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical 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.
Remediation
Check the references section for vendor advisories and patches from apache. Update log4j to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| apache | log4j | >= 2.0, < 2.3.1 | Affected |
| sonicwall | email_security | 0 | Affected |
| sonicwall | network_security_manager | >= 2.0, < 3.0 | Affected |
| sonicwall | web_application_firewall | >= 3.0.0, < 3.1.0 | Affected |
| sonicwall | 6bk1602-0aa12-0tp0_firmware | >= 0, < 2.7.0 | Affected |
| sonicwall | 6bk1602-0aa22-0tp0_firmware | >= 0, < 2.7.0 | Affected |
| sonicwall | 6bk1602-0aa32-0tp0_firmware | >= 0, < 2.7.0 | Affected |
| sonicwall | 6bk1602-0aa42-0tp0_firmware | >= 0, < 2.7.0 | Affected |
| sonicwall | 6bk1602-0aa52-0tp0_firmware | >= 0, < 2.7.0 | Affected |
References
Frequently Asked Questions
What is CVE-2021-45105?
CVE-2021-45105 is a medium-severity vulnerability affecting apache log4j. It was published on December 18, 2021 and has a CVSS 3.1 base score of 5.9 (MEDIUM).
How severe is CVE-2021-45105?
This vulnerability has a CVSS 3.1 base score of 5.9, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2021-45105?
Check the references section for vendor advisories and patches from apache. Update log4j to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2021-45105?
CyberStrike's AI-powered security agents can automatically detect CVE-2021-45105 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
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