Is CVE-2021-45105 actively exploited?

Yes. CVE-2021-45105 is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, which means exploitation in the wild has been confirmed.

Can CVE-2021-45105 be exploited remotely?

The attack vector of CVE-2021-45105 has not been classified yet.

What is the CVSS score of CVE-2021-45105?

CVE-2021-45105 has not received a CVSS score yet.

HOME VULNERABILITIESCVE-2021-45105

UNKNOWNCISA KEVIN THE WILD

CVE-2021-45105

Published: April 11, 2026

EPSS:70.43%probability of exploitation in 30 daysPercentile:98.7th

Official 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.

NVD Source

Technical Analysis

CVE-2021-45105 requires local access, meaning attackers must already have a foothold on the target system.

Exploitation requires some privileges, which limits the exposure to scenarios where an attacker has already gained initial access.

CISA has added CVE-2021-45105 to the Known Exploited Vulnerabilities (KEV) catalog, confirming active exploitation in the wild. U.S. federal agencies are required to patch this within the mandated timeframe, and all organizations should treat remediation as urgent.