Risk Letters

Exploited vulnerability

CVE-2021-45046

TLP:CLEAR

Apache Log4j2 Deserialization of Untrusted Data Vulnerability

Apache Log4j2 contains a deserialization of untrusted data vulnerability due to the incomplete fix of CVE-2021-44228, where the Thread Context Lookup Pattern is vulnerable to remote code execution in certain non-default configurations.

Facts

  • Vendor: Apache
  • Product: Log4j2
  • CVSS: 9
  • EPSS (probability of exploitation within 30 days): 100 %
  • On CISA's Known Exploited Vulnerabilities list since: 1 May 2023
  • First known exploitation: 1 May 2023
  • Used in ransomware campaigns (per CISA): Yes
  • CISA's deadline for US federal agencies: 22 May 2023
  • Weakness: CWE-917
  • First seen by Risk Letters: 1 May 2023

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Data: NVD (public domain), CISA KEV, FIRST EPSS, MITRE ATT&CK, AlienVault OTX. NVD