Apache Log4j2 Deserialization of Untrusted Data Vulnerability
Apache · Log4j2
CVSS 9
EPSS 100%
no public exploit indexed
ransomware
Fix deadline passed 22 May 2023
What it is
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.
Why we say that
- Linked by CISA to known ransomware campaigns
- EPSS puts exploitation in the next 30 days at 100%
- CISA's federal remediation deadline (2023-05-22) has passed
- CVSS 9 critical
- Listed in the CISA Known Exploited Vulnerabilities catalogue
Every line above comes from a named public source. Where the evidence is thin, we say so rather than inventing confidence — see methodology.
What to do
Apply updates per vendor instructions.
What it costs when this goes wrong
This is where UK enforcement meets the vulnerability record. This vulnerability is used in ransomware campaigns; here is what ransomware has cost UK organisations at the regulator.
- Advanced Computer Software Group Limited The Information Commissioner’s Office (ICO) has fined Advanced Computer Software Group Ltd (Advanced) £3.07m for security failings…
- Optionis Group Limited The data controller suffered a ransomware attack, which resulted in the exfiltration of personal data. A reprimand was issued in r…