Evidence dossier

CVE-2021-45046

Apache Log4j2 Thread Context Message Pattern and Context Lookup Pattern vulnerable to a denial of service attack

72.7–97.5Priority evidence range

As known Jul 19, 2026, 5:00 AM UTCgen-56ccdaf9

Normalized restatement

It was found that the fix to address CVE-2021-44228 in Apache Log4j 2.15.0 was incomplete in certain non-default configurations. This could allows attackers with control over Thread Context Map (MDC) input data when the logging configuration uses a non-default Pattern Layout with either a Context Lookup (for example, $${ctx:loginId}) or a Thread Context Map pattern (%X, %mdc, or %MDC) to craft malicious input data using a JNDI Lookup pattern resulting in an information leak and remote code execution in some environments and local code execution in all environments. Log4j 2.16.0 (Java 8) and 2.12.2 (Java 7) fix this issue by removing support for message lookup patterns and disabling JNDI functionality by default.

State: PUBLISHED
Published: Dec 14, 2021
Updated: Oct 21, 2025
Evidence coverage: 72%

CISA KEVCatalog member

Apply updates per vendor instructions.

FIRST EPSS99.98%

2026-07-18 · v2026.06.15 · percentile 100.0%

Source stateConflict visible

Distinct CVSS assessments remain side by side; none are averaged.

Source comparison

Who said what

apacheoriginal assertion

container

Apache Log4j2 Thread Context Message Pattern and Context Lookup Pattern vulnerable to a denial of service attack

Jul 19, 2026Original evidence ↗

CISA-ADPindependent enrichment

container

CISA ADP Vulnrichment

Jul 19, 2026Original evidence ↗

CVEderivative copy

container

CVE Program Container

Jul 19, 2026Original evidence ↗

CISA KEVoriginal assertion

observed_exploitation

Apache Log4j2 Deserialization of Untrusted Data Vulnerability

Jul 19, 2026Original evidence ↗

FIRST EPSSoriginal assertion

model_probability

Probability 0.999770000000; percentile 0.999800000000

Jul 19, 2026Original evidence ↗

Applicability

Cited product scope

Trace impact →

Apache Software FoundationApache Log4j

[{"status": "affected", "version": "Apache Log4j2", "lessThan": "2.16.0", "versionType": "custom"}]unknown

Unknown vendorUnknown product

cpe:2.3:a:apache:log4j:*:*:*:*:*:*:*:*; start including 2.0.1; end excluding 2.12.2supported

Unknown vendorUnknown product

cpe:2.3:a:apache:log4j:*:*:*:*:*:*:*:*; start including 2.13.0; end excluding 2.16.0supported

Unknown vendorUnknown product

cpe:2.3:a:apache:log4j:2.0:-:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:apache:log4j:2.0:beta9:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:apache:log4j:2.0:rc1:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:apache:log4j:2.0:rc2:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:cvat:computer_vision_annotation_tool:-:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:intel:audio_development_kit:-:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:intel:datacenter_manager:-:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:intel:genomics_kernel_library:-:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:intel:oneapi:-:*:*:*:*:eclipse:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:intel:secure_device_onboard:-:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:intel:sensor_solution_firmware_development_kit:-:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:intel:system_debugger:-:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:intel:system_studio:-:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:captial:*:*:*:*:*:*:*:*; end excluding 2019.1supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:captial:2019.1:-:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:captial:2019.1:sp1912:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:comos:*:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:desigo_cc_advanced_reports:4.0:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:desigo_cc_advanced_reports:4.1:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:desigo_cc_advanced_reports:4.2:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:desigo_cc_advanced_reports:5.0:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:desigo_cc_advanced_reports:5.1:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:desigo_cc_info_center:5.0:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:desigo_cc_info_center:5.1:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:e-car_operation_center:*:*:*:*:*:*:*:*; end excluding 2021-12-13supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:energy_engage:3.1:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:energyip:8.5:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:energyip:8.6:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:energyip:8.7:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:energyip:9.0:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:energyip_prepay:3.7:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:energyip_prepay:3.8:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:gma-manager:*:*:*:*:*:*:*:*; end excluding 8.6.2j-398supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:head-end_system_universal_device_integration_system:*:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:industrial_edge_management:*:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:industrial_edge_management_hub:*:*:*:*:*:*:*:*; end excluding 2021-12-13supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:logo\!_soft_comfort:*:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:mendix:*:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:mindsphere:*:*:*:*:*:*:*:*; end excluding 2021-12-11supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:navigator:*:*:*:*:*:*:*:*; end excluding 2021-12-13supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:nx:*:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:opcenter_intelligence:*:*:*:*:*:*:*:*; end including 3.2supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:operation_scheduler:*:*:*:*:*:*:*:*; end including 1.1.3supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:sentron_powermanager:4.1:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:sentron_powermanager:4.2:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:siguard_dsa:4.2:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:siguard_dsa:4.3:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:siguard_dsa:4.4:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:sipass_integrated:2.80:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:sipass_integrated:2.85:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:siveillance_command:*:*:*:*:*:*:*:*; end including 4.16.2.1supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:siveillance_control_pro:*:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:siveillance_identity:1.5:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:siveillance_identity:1.6:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:siveillance_vantage:*:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:siveillance_viewpoint:*:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:solid_edge_cam_pro:*:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:solid_edge_harness_design:*:*:*:*:*:*:*:*; end excluding 2020supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:solid_edge_harness_design:2020:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:solid_edge_harness_design:2020:-:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:solid_edge_harness_design:2020:sp2002:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:spectrum_power_4:*:*:*:*:*:*:*:*; end excluding 4.70supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:spectrum_power_4:4.70:-:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:spectrum_power_4:4.70:sp7:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:spectrum_power_4:4.70:sp8:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:spectrum_power_7:*:*:*:*:*:*:*:*; end excluding 2.30supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:spectrum_power_7:2.30:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:spectrum_power_7:2.30:-:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:spectrum_power_7:2.30:sp2:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:teamcenter:*:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:tracealertserverplus:*:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:vesys:*:*:*:*:*:*:*:*; end excluding 2019.1supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:vesys:2019.1:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:vesys:2019.1:-:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:vesys:2019.1:sp1912:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:xpedition_enterprise:-:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:siemens:xpedition_package_integrator:-:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:sonicwall:email_security:*:*:*:*:*:*:*:*; end excluding 10.0.12supported

Unknown vendorUnknown product

cpe:2.3:h:siemens:6bk1602-0aa12-0tp0:-:*:*:*:*:*:*:*constrained

Unknown vendorUnknown product

cpe:2.3:h:siemens:6bk1602-0aa22-0tp0:-:*:*:*:*:*:*:*constrained

Unknown vendorUnknown product

cpe:2.3:h:siemens:6bk1602-0aa32-0tp0:-:*:*:*:*:*:*:*constrained

Unknown vendorUnknown product

cpe:2.3:h:siemens:6bk1602-0aa42-0tp0:-:*:*:*:*:*:*:*constrained

Unknown vendorUnknown product

cpe:2.3:h:siemens:6bk1602-0aa52-0tp0:-:*:*:*:*:*:*:*constrained

Unknown vendorUnknown product

cpe:2.3:h:siemens:sppa-t3000_ses3000:-:*:*:*:*:*:*:*constrained

Unknown vendorUnknown product

cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:o:siemens:6bk1602-0aa12-0tp0_firmware:*:*:*:*:*:*:*:*; end excluding 2.7.0supported

Unknown vendorUnknown product

cpe:2.3:o:siemens:6bk1602-0aa22-0tp0_firmware:*:*:*:*:*:*:*:*; end excluding 2.7.0supported

Unknown vendorUnknown product

cpe:2.3:o:siemens:6bk1602-0aa32-0tp0_firmware:*:*:*:*:*:*:*:*; end excluding 2.7.0supported

Unknown vendorUnknown product

cpe:2.3:o:siemens:6bk1602-0aa42-0tp0_firmware:*:*:*:*:*:*:*:*; end excluding 2.7.0supported

Unknown vendorUnknown product

cpe:2.3:o:siemens:6bk1602-0aa52-0tp0_firmware:*:*:*:*:*:*:*:*; end excluding 2.7.0supported

Unknown vendorUnknown product

cpe:2.3:o:siemens:sppa-t3000_ses3000_firmware:*:*:*:*:*:*:*:*supported

Assessments

CVSS by origin

9.0

nvd@nist.govCVSS 3.1 · role PrimaryCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H

5.1

nvd@nist.govCVSS 2.0 · role PrimaryAV:N/AC:H/Au:N/C:P/I:P/A:P

9.0

134c704f-9b21-4f2e-91b3-4a467353bcc0CVSS 3.1 · role SecondaryCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H

9.0

CISA-ADPCVSS 3.1 · role unknownCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H

Limitations and unknowns

KEV membership is authoritative for the catalog, not proof of exposure in any environment.
EPSS is a dated model probability and not an individual-environment prediction.
Affected or fixed status applies only to the exact cited product and version scope; unresolved scope remains unknown.
NVD-carried upstream facts remain derivative and are not independent corroboration.
Only NVD metrics validated under the generation-bound calculator are Public Priority eligible; direct CVE record metrics remain display-only.
NVD CVSS source eligibility is closed: NVD-authored, exact record-source, or registered same-CVE container origin; unmapped sources remain display-only.
Factor D is unknown in Public Core because no accepted canonical mapping-obligation ledger is present.
Core replay supports the active and immediately prior generation; retrospective valid-at replay is deferred.