Reference page — cumulative record through Sunday, October 4, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
AV AC PR UI S C I A CVSS EPSS %ile KEV N L N N U H H H 9.8 .9927 99.9 YES
AFFECTED Product Versions Fixed Apache Tomcat Apache Tomcat 9.0.0.M1 to 9.0.0.30 – —
TIMELINE Dec 2 Reserved by apache Feb 24 Published (CNA: apache) Mar 3 Added to CISA KEV, remediation due 2022-03-17 Aug 25 EXPLOIT PUBLISHED — CVE-2020-1938 (Apache Tomcat). Public exploit reference added.
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.
| Date | Event | Detail |
|---|---|---|
| December 2, 2019 | Reserved | Reserved by apache |
| February 24, 2020 | Published | Published (CNA: apache) |
| March 3, 2022 | KEV ADDED | Added to CISA KEV, remediation due 2022-03-17 |
| August 25, 2026 | EXPLOIT PUBLISHED | EXPLOIT PUBLISHED — CVE-2020-1938 (Apache Tomcat). Public exploit reference added. |
| Vendor | Product / Package | Ecosystem | Version introduced | Fixed |
|---|---|---|---|---|
| Apache | Apache Tomcat | — | Apache Tomcat 9.0.0.M1 to 9.0.0.30 | — |
Authoritative record: CVE-2020-1938 at cve.org
Vendors: apache
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2020-1938 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Sunday, October 4, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.
