Vulnerability Intelligence Report
Apache Log4j2 does not always protect from infinite recursion in lookup evaluation
CVE-2021-45105
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 Active Exploit Signals
CVSS Base Score
5.9
MEDIUM
Exploitability:2.3
Impact Score:3.6
EPSS Probability:100.00%
Executive Threat Verdict
Evaluating...
Evaluating Threat Landscape...
Assessing known weaponization, exploitation telemetry, and federal advisories.
Attack Surface
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Authentication
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Weaponization
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SSVC Action
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Affected Products & Versions
| Vendor | Product | Affected Versions |
|---|---|---|
| Apache Software Foundation | Apache Log4j2 | log4j-core < 2.17.0 (affected) |
References & Technical Advisories
No reference links found.
Threat Intelligence Signals
EPSS Score
99.999%
GitHub Advisory
Identity & Timeline
| Status | PUBLISHED |
| Assigning Authority | Apache Software Foundation · Vendor · USA |
| Reserved | 2021-12-16T00:00:00 |
| Published | 2021-12-18T11:55:08 |
| Last Updated | 2026-05-29T11:45:26 |
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