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Weekly Signal
Live intelligence Updated 19 Aug 2026 · 20:27 UTC

Apache, Blackberry, Debian +4 more · Geode, Tomcat, Good Control +18 more

CVE-2020-1938

Apache Tomcat Improper Privilege Management Vulnerability

Recommended action

Treat this as an immediate remediation priority. Apply updates per vendor instructions.

View response plan
CVSS9.8
EPSS99.3%
KEVYes
ExploitationConfirmed exploitation
PatchPatch or guidance available ↓

Assessment

Why it matters

CISA lists this vulnerability as known to be exploited; exploitation is confirmed; EPSS is 99.3%; technical severity is CVSS 9.8.

When using the Apache JServ Protocol (AJP), care must be taken when trusting incoming connections to Apache Tomcat. Tomcat treats AJP connections as having higher trust than, for example, a similar HTTP connection. If such connections are available to an attacker, they can be exploited in ways that may be surprising. In Apache Tomcat 9.0.0.M1 to 9.0.0.30, 8.5.0 to 8.5.50 and 7.0.0 to 7.0.99, Tomcat shipped with an AJP Connector enabled by default that listened on all configured IP addresses. It was expected (and recommended in the security guide) that this Connector would be disabled if not required. This vulnerability report identified a mechanism that allowed: - returning arbitrary files from anywhere in the web application - processing any file in the web application as a JSP Further, if the web application allowed file upload and stored those files within the web application (or the attacker was able to control the content of the web application by some other means) then this, along with the ability to process a file as a JSP, made remote code execution possible. It is important to note that mitigation is only required if an AJP port is accessible to untrusted users. Users wishing to take a defence-in-depth approach and block the vector that permits returning arbitrary files and execution as JSP may upgrade to Apache Tomcat 9.0.31, 8.5.51 or 7.0.100 or later. A number of changes were made to the default AJP Connector configuration in 9.0.31 to harden the default configuration. It is likely that users upgrading to 9.0.31, 8.5.51 or 7.0.100 or later will need to make small changes to their configurations.

Who should care

  • Teams operating Geode, Tomcat, Good Control +18 more
  • Vulnerability and exposure management teams
  • Security operations teams monitoring exploitation activity

Response plan

What I would do

  1. Confirm whether Geode, Tomcat, Good Control +18 more is present in the environment.
  2. Identify affected versions and establish whether vulnerable services are exposed or reachable.
  3. Apply updates per vendor instructions.
  4. Review relevant security telemetry for evidence of attempted or successful exploitation.
  5. Document the remediation decision and track it to verified completion.

Vendor remediation

Patch and remediation links

Use the vendor source below to confirm the correct fixed version, package or mitigation for your affected product.

Technical details

CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CWE
Not classified
Affected versions
Apache Geode (Version: 1.12.0); Apache Tomcat (Start Including: 9.0.0, End Excluding: 9.0.31); Blackberry Good Control (End Including: 5.2.58.38); Blackberry Workspaces Server (Version: 9.0); Debian Debian Linux (Version: 10.0); Fedoraproject Fedora (Version: 32); Netapp Data Availability Services (Version: -); Netapp Oncommand System Manager (Start Including: 3.0.0, End Including: 3.1.3)
Published
24 February 2020
Attack vector
Network
Privileges required
None
User interaction
None

Signal timeline

  1. CVE published
  2. Added to CISA KEV
  3. Latest EPSS score: 99.3%
  4. Signal calculated at 85

External references

Live public intelligence This assessment combines public-source evidence. Validate the affected product, version and exposure against your own environment before making a risk decision.