CVE-2020-1938

9.8 CRITICAL CISA KEV - Actively Exploited
Published: February 24, 2020 Modified: October 27, 2025

Description

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.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2020-05/msg00002.html
Source: security@apache.org
Mailing List Third Party Advisory
http://support.blackberry.com/kb/articleDetail?articleNumber=000062739
Source: security@apache.org
Third Party Advisory
https://lists.debian.org/debian-lts-announce/2020/03/msg00006.html
Source: security@apache.org
Third Party Advisory
https://lists.debian.org/debian-lts-announce/2020/05/msg00026.html
Source: security@apache.org
Third Party Advisory
https://security.gentoo.org/glsa/202003-43
Source: security@apache.org
Third Party Advisory
https://security.netapp.com/advisory/ntap-20200226-0002/
Source: security@apache.org
Third Party Advisory
https://www.debian.org/security/2020/dsa-4673
Source: security@apache.org
Third Party Advisory
https://www.debian.org/security/2020/dsa-4680
Source: security@apache.org
Third Party Advisory
https://www.oracle.com/security-alerts/cpujan2021.html
Source: security@apache.org
Patch Third Party Advisory
https://www.oracle.com/security-alerts/cpujul2020.html
Source: security@apache.org
Patch Third Party Advisory
https://www.oracle.com/security-alerts/cpuoct2020.html
Source: security@apache.org
Patch Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2020-03/msg00025.html
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2020-05/msg00002.html
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List Third Party Advisory
http://support.blackberry.com/kb/articleDetail?articleNumber=000062739
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://lists.debian.org/debian-lts-announce/2020/03/msg00006.html
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://lists.debian.org/debian-lts-announce/2020/05/msg00026.html
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://security.gentoo.org/glsa/202003-43
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://security.netapp.com/advisory/ntap-20200226-0002/
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://www.debian.org/security/2020/dsa-4673
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://www.debian.org/security/2020/dsa-4680
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://www.oracle.com/security-alerts/cpujan2021.html
Source: af854a3a-2127-422b-91ae-364da2661108
Patch Third Party Advisory
https://www.oracle.com/security-alerts/cpujul2020.html
Source: af854a3a-2127-422b-91ae-364da2661108
Patch Third Party Advisory
https://www.oracle.com/security-alerts/cpuoct2020.html
Source: af854a3a-2127-422b-91ae-364da2661108
Patch Third Party Advisory
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-1938
Source: 134c704f-9b21-4f2e-91b3-4a467353bcc0
US Government Resource

103 reference(s) from NVD

Quick Stats

CVSS v3 Score
9.8 / 10.0
EPSS (Exploit Probability)
94.5%
100th percentile
Exploitation Status
Actively Exploited
Remediation due: 2022-03-17

Affected Vendors

debian blackberry netapp fedoraproject oracle apache opensuse