CVE-2021-44228
Apache Log4j2 contains a vulnerability where JNDI features do not protect against attacker-controlled JNDI-related endpoints, allowing for remote code execution.
Apache Log4j2 2.0-beta9 through 2.15.0 (excluding security releases 2.12.2, 2.12.3, and 2.3.1) JNDI features used in configuration, log messages, and parameters do not protect against attacker controlled LDAP and other JNDI related endpoints. An attacker who can control log messages or log message parameters can execute arbitrary code loaded from LDAP servers when message lookup substitution is enabled. From log4j 2.15.0, this behavior has been disabled by default. From version 2.16.0 (along with 2.12.2, 2.12.3, and 2.3.1), this functionality has been completely removed. Note that this vulnerability is specific to log4j-core and does not affect log4net, log4cxx, or other Apache Logging Services projects.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H- packetstormsecurity.com/files/165225/Apache-Log4j2-2.14.1-Remote-Code-Execution.htmlThird Party AdvisoryVDB Entry
- packetstormsecurity.com/files/165260/VMware-Security-Advisory-2021-0028.htmlThird Party AdvisoryVDB Entry
- packetstormsecurity.com/files/165261/Apache-Log4j2-2.14.1-Information-Disclosure.htmlExploitThird Party Advisory
- packetstormsecurity.com/files/165270/Apache-Log4j2-2.14.1-Remote-Code-Execution.htmlExploitThird Party Advisory
- packetstormsecurity.com/files/165281/Log4j2-Log4Shell-Regexes.htmlThird Party AdvisoryVDB Entry
- packetstormsecurity.com/files/165282/Log4j-Payload-Generator.htmlThird Party AdvisoryVDB Entry
- packetstormsecurity.com/files/165306/L4sh-Log4j-Remote-Code-Execution.htmlThird Party AdvisoryVDB Entry
- packetstormsecurity.com/files/165307/Log4j-Remote-Code-Execution-Word-Bypassing.htmlThird Party AdvisoryVDB Entry
- packetstormsecurity.com/files/165311/log4j-scan-Extensive-Scanner.htmlBroken LinkThird Party Advisory
- packetstormsecurity.com/files/165371/VMware-Security-Advisory-2021-0028.4.htmlExploitThird Party Advisory
- packetstormsecurity.com/files/165532/Log4Shell-HTTP-Header-Injection.htmlExploitThird Party Advisory
- packetstormsecurity.com/files/165642/VMware-vCenter-Server-Unauthenticated-Log4Shell-JNDI-Injection-Remote-Code-Execution.htmlExploitThird Party Advisory
Actively exploited and used by ransomware crews. Patch immediately.
- Exploitation
- Confirmed in the wild (CISA KEV)
- Federal remediation deadline
- Overdue by 1767 days
- Ransomware
- Used in known ransomware campaigns
- CVSS
- 10.0 CRITICAL
- EPSS (30-day exploit probability)
- 100.0% · top 1% of all CVEs
- Weakness
- CWE-20
- Attack vector
- Network, remotely reachable
- Preconditions
- No privileges and no user interaction
- 1.For all affected software assets for which updates exist, the only acceptable remediation actions are: 1) Apply updates; OR 2) remove affected assets from agency networks. Temporary mitigations using one of the measures provided at https://www.cisa.gov/uscert/ed-22-02-apache-log4j-recommended-mitigation-measures are only acceptable until updates are available.
- 2.Treat as emergency change: patch or isolate internet-facing instances first.
- 3.Review exposure: confirm which instances are reachable from the internet and restrict access until patched.
- 4.Hunt for compromise: review logs for the disclosure window, not just from the patch date.
- 5.Verify offline/immutable backups and segment the affected systems. This flaw is used for ransomware initial access.
Assessment is derived automatically from the live signals above; verify against your own asset inventory.