CVE Intelligence
CISA KEV Critical exploit reference

CVE-2020-1938 — Apache Tomcat Improper Privilege Management Vulnerability

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.

Published Feb 24, 2020 · Updated Oct 13, 2026 · Sources: CISA Known Exploited Vulnerabilities, NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP, GitHub Security Advisories · CNA: apache

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

CISA KEV · Mar 3, 2022 Detection templates (Nuclei) · 1Metasploit modules · 1Exploit-DB · 2Proofs of concept on GitHub · 40
How the score was calculated
  • Confirmed exploitation (CISA KEV)+35
  • Public exploit/PoC (nuclei, metasploit, exploitdb, github)+20
  • EPSS 99.3% (30-day exploitation probability)+15
  • Technical severity (critical)+10
  • Automatable exploitation (SSVC)+3

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation
Confirmed
CISA KEV, listed Mar 3, 2022
EPSS FIRST
99.27%
ahead of 100% of scored CVEs · Oct 14, 2026
Affects
Apache Software Foundation
Geode and 21 more
CVSS base
9.8
Critical · 4 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation
Active
none · proof-of-concept · active
Automatable
Yes
can an attacker script the kill-chain steps
Technical impact
Total
partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

  • Documented patch — lists.apache.org (NIST National Vulnerability Database)
  • Documented patch — lists.apache.org (NIST National Vulnerability Database)
  • Documented patch — lists.apache.org (NIST National Vulnerability Database)
  • Documented patch — www.oracle.com (NIST National Vulnerability Database)
  • Documented patch — www.oracle.com (NIST National Vulnerability Database)
  • Documented patch — www.oracle.com (NIST National Vulnerability Database)
  • Maven Org.apache.tomcat.embed:tomcat-embed-core: fixed in version 9.0.31 — github.com (GitHub Security Advisories)
  • Maven Org.apache.tomcat.embed:tomcat-embed-core: fixed in version 8.5.51 — github.com (GitHub Security Advisories)
  • Maven Org.apache.tomcat.embed:tomcat-embed-core: fixed in version 7.0.100 — github.com (GitHub Security Advisories)

CISA required action CISA

Apply updates per vendor instructions.

US federal deadline: Mar 17, 2022 — passed 1673 day(s) ago

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

  1. Identify exposed assets running the affected vendor/product/version combinations (Apache Software Foundation Geode, Apache Software Foundation Tomcat, Blackberry Good Control…).
  2. Treat as emergency remediation: the CVE is in CISA KEV (confirmed exploitation).
  3. The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
  4. Apply the fixed version or the patch documented under Remediation.
  5. EPSS ahead of 100% of scored CVEs: prioritize it in the patch queue.
  6. Search available logs for exploit probes, errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Apache Software Foundation Geode version 1.12.0 Vulnerable NIST National Vulnerability Database
Apache Software Foundation Tomcat version 7.0.0 to 7.0.99version 8.5.0 to 8.5.50version Apache Tomcat 9.0.0.M1 to 9.0.0.30 Vulnerable CVE Program (cve.org) e CISA ADP
Apache Software Foundation Tomcat ≥ 9.0.0 and < 9.0.31≥ 8.5.0 and < 8.5.51≥ 7.0.0 and < 7.0.100 Vulnerable NIST National Vulnerability Database
Blackberry Good Control ≤ 5.2.58.38 Vulnerable NIST National Vulnerability Database
Blackberry Workspaces Server version 7.0.1version 7.1.2version 8.1.0version 9.0 Vulnerable NIST National Vulnerability Database
Debian Debian Linux version 10.0version 9.0version 8.0 Vulnerable NIST National Vulnerability Database
Fedoraproject Fedora version 31version 32version 30 Vulnerable NIST National Vulnerability Database
Netapp Data Availability Services versions not specified by the source Vulnerable NIST National Vulnerability Database
Netapp Oncommand System Manager ≥ 3.0.0 and ≤ 3.1.3 Vulnerable NIST National Vulnerability Database
Opensuse Leap version 15.1 Vulnerable NIST National Vulnerability Database
Oracle Agile Engineering Data Management version 6.2.1.0 Vulnerable NIST National Vulnerability Database
Oracle Agile Product Lifecycle Management version 9.3.6version 9.3.3version 9.3.5 Vulnerable NIST National Vulnerability Database
Oracle Communications Element Manager version 8.2.1version 8.2.0version 8.1.1 Vulnerable NIST National Vulnerability Database
Oracle Communications Instant Messaging Server version 10.0.1.4.0 Vulnerable NIST National Vulnerability Database
Oracle Health Sciences Empirica Inspections version 1.0.1.2 Vulnerable NIST National Vulnerability Database
Oracle Health Sciences Empirica Signal version 7.3.3 Vulnerable NIST National Vulnerability Database
Oracle Hospitality Guest Access version 4.2.1version 4.2.0 Vulnerable NIST National Vulnerability Database
Oracle Instantis Enterprisetrack ≥ 17.1 and ≤ 17.3 Vulnerable NIST National Vulnerability Database
Oracle Mysql Enterprise Monitor ≥ 8.0.0 and ≤ 8.0.20≤ 4.0.12 Vulnerable NIST National Vulnerability Database
Oracle Siebel Ui Framework ≤ 20.5 Vulnerable NIST National Vulnerability Database
Oracle Transportation Management version 6.3.7 Vulnerable NIST National Vulnerability Database
Oracle Workload Manager version 18cversion 19cversion 12.2.0.1 Vulnerable NIST National Vulnerability Database
Maven Org.apache.tomcat.embed:tomcat-embed-core ≥ 9.0.0 and < 9.0.31≥ 8.0.0 and < 8.5.51≥ 7.0.0 and < 7.0.100 Vulnerable GitHub Security Advisories

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactScored by
9.8 CVSS 3.1 Critical 3.9 5.9 nvd@nist.gov via NIST National Vulnerability Database
9.8 CVSS 3.1 Critical 3.9 5.9 134c704f-9b21-4f2e-91b3-4a467353bcc0 via NIST National Vulnerability Database
9.8 CVSS 3.1 Critical — — GitHub, Inc. via GitHub Security Advisories
9.8 CVSS 3.1 Critical — — CISA-ADP via CVE Program (cve.org) e CISA ADP
7.5 CVSS 2.0 High 10.0 6.4 nvd@nist.gov via NIST National Vulnerability Database
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H (score shown at the top: nvd@nist.gov)

CISA KEV details CISA

CISA lists a CVE once it has evidence of exploitation against real targets.

Listed
Mar 3, 2022
Federal deadline
Mar 17, 2022
passed 1673 day(s) ago
Ransomware use
Unknown

CISA records ransomware use only for campaigns it has confirmed, so “Unknown” means unrecorded, not ruled out. The deadline binds US federal agencies; for everyone else it is a reference date.

Public exploits, PoCs and detection templates

Public code that demonstrates or tests the flaw raises the odds of mass exploitation — and Nuclei templates help find vulnerable assets in your environment.

Detection templates (Nuclei)
Metasploit modules
Exploit-DB
Proofs of concept on GitHub — 40 repositories; showing the 10 most starred

Warning: public PoCs are sometimes disguised malware. Use them only for authorized testing in an isolated environment. This portal does not host exploit code — it only points to the sources.

EPSS over time FIRST

Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 99.27%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

  • Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
  • Hunt retroactively in logs from before Mar 3, 2022 (KEV listing): exploitation may have started earlier.
web/proxy/WAF logsnetwork IDS/IPS

Timeline

What happened to this CVE, newest first.

  • 2026
  • Fix documented
    Oct 13, 2026 · GitHub Security Advisories
  • Affected products added · maven/org.apache.tomcat.embed:tomcat-embed-core
    Oct 13, 2026 · GitHub Security Advisories
  • Affected products added · apache/apache tomcat
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • SSVC assessment updated
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • Record published
    Oct 13, 2026
  • Fix documented
    Oct 13, 2026 · NIST National Vulnerability Database
  • Affected products added · apache/geode, apache/tomcat, fedoraproject/fedora, oracle/agile engineering data management, oracle/agile product lifecy
    Oct 13, 2026 · NIST National Vulnerability Database
  • CVSS changed · 9.8
    Oct 13, 2026 · NIST National Vulnerability Database
  • Source status changed · → Analyzed
    Oct 13, 2026 · NIST National Vulnerability Database
  • Added to CISA KEV (detected)
    Oct 13, 2026 · CISA Known Exploited Vulnerabilities
  • Record created in this database
    Oct 13, 2026 · CISA Known Exploited Vulnerabilities
  • 2022
  • Added to CISA KEV catalog
    Mar 2, 2022 · CISA
  • 2020
  • CVE published
    Feb 24, 2020 · apache

Source activity

Repeated readings are counted rather than listed.

  • 2× References added · Oct 13, 2026 – Oct 13, 2026
  • 1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

96 on the record

Elsewhere on this site

Apache Software Foundation
every CVE for this vendor
2022-03
what else CISA listed that month

Related CVEs (same products)

  • CVE-2026-103371 Apache Geode: Management REST API: Insertion of Sensitive Information into Log File 8d
  • CVE-2026-87266 Improper Access Control in Oracle Agile Product Lifecycle Management Sep 15, 2026
  • CVE-2026-87257 Improper Access Control in Oracle Agile Product Lifecycle Management Sep 15, 2026
  • CVE-2026-87253 Improper Access Control in Oracle Agile Product Lifecycle Management Sep 15, 2026
  • CVE-2026-87254 Improper Access Control in Oracle Agile Product Lifecycle Management Sep 15, 2026
  • CVE-2026-87256 Improper Access Control in Oracle Agile Product Lifecycle Management Sep 15, 2026

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

  • No CWE classification.
  • No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
  • No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
  • No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2020-1938 is "Apache Tomcat Improper Privilege Management Vulnerability", rated Critical. It affects Geode (Apache Software Foundation); versions are in the scope table. It is in CISA KEV: there is evidence of real-world exploitation. CVSS 9.8 describes technical severity. EPSS 99.27% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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