`CVE-2021-33037` Apache Tomcat

Affected software	Apache Tomcat
Severity	5.3 Medium CVSS 3.1 2 scores
Fixed in	`10.0.7`, `9.0.48`, `8.5.68`
Weakness	CWE-444
Published	12 Jul 2021
Updated	8 Oct 2026

Description

Apache Tomcat 10.0.0-M1 to 10.0.6, 9.0.0.M1 to 9.0.46 and 8.5.0 to 8.5.66 did not correctly parse the HTTP transfer-encoding request header in some circumstances leading to the possibility to request smuggling when used with a reverse proxy. Specifically: - Tomcat incorrectly ignored the transfer encoding header if the client declared it would only accept an HTTP/1.0 response; - Tomcat honoured the identify encoding; and - Tomcat did not ensure that, if present, the chunked encoding was the final encoding.

Exploitation status

Forecast only (75% 30-day chance)

No exploit has been reported in the sources we check. EPSS puts this CVE in the top 0.49% of all scored CVEs. That is a model's forecast, not a report of exploitation.

CISA KEV not listed
VulnCheck KEV not listed
CISA Vulnrichment exploitation: none
Indexed PoC none indexed
EPSS 75% chance in 30 days A model's forecast, not a report of exploitation. Higher than 99.5% of all scored CVEs.

Waratek protection

No exploit published

Within Waratek scope. In the sources we check, nobody has published exploit code for this CVE or reported it being exploited.

VRT has not found a public code change for this CVE yet.

Protection none
Action not pursued
Review human Researcher
Record active

Decided by	Manual classification of this CVE in the legacy dataset
Finding	A manual classification set this CVE's status to No source fix or exploit.

Decided by

Manual classification of this CVE in the legacy dataset

Finding

A manual classification set this CVE's status to No source fix or exploit.

CVSS

5.3 MEDIUM v3.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N 2 metrics

We show the highest score from the newest CVSS version. Scores from different versions can't be compared, and the first score listed is sometimes a 0.0 placeholder.

Version Score Band Vector Assigner Type

CVSS 3.1 5.3 MEDIUM CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N NVD Primary published

CVSS 2.0 5.0 none AV:N/AC:L/Au:N/C:N/I:P/A:N NVD Primary

Version	Score	Band	Vector	Assigner	Type
CVSS 3.1	5.3	MEDIUM	`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N`	NVD	Primary	published
CVSS 2.0	5.0	none	`AV:N/AC:L/Au:N/C:N/I:P/A:N`	NVD	Primary

Affected software and releases

Oracle advisories

Advisory	Type	Quarter	Products Oracle names in its risk matrix
Oracle Critical Patch Update April 2025 ↗	CPU	2025-Q2	Oracle Autonomous Health Framework / Trace File Analyzer (Apache Tomcat) (23.8.0-23.11.0, 24.1.0-24.11.0, 25.1.0, 25.2.0)
Oracle Critical Patch Update April 2022 ↗	CPU	2022-Q2	Oracle Fusion Middleware / MFT Runtime Server (Apache Tomcat) (12.2.1.3.0, 12.2.1.4.0) Oracle HealthCare Applications / Datastudio (Apache Tomcat) (4.1.0)
Oracle Critical Patch Update January 2022 ↗	CPU	2022-Q1	Oracle Communications / SCP (Apache Tomcat) (1.14.0) Oracle Graph Server and Client / Packaging/Install (Apache Tomcat) (Prior to 21.4) Oracle Supply Chain / Security (Apache Tomcat) (9.3.6) Oracle Utilities Applications / Tools (Apache Tomcat) (6.0.0.1.1, 6.0.0.2.2, 6.0.0.3.1)
Oracle Critical Patch Update October 2021 ↗	CPU	2021-Q4	Oracle Communications / MediationServer (Apache Tomcat) (12.5.0) Oracle Communications / Platform (Apache Tomcat) (8.0.0.0-8.5.0.0) Oracle Communications / Reports (Apache Tomcat) (8.0.0.0-8.2.4.0) Oracle Communications / Route Manager (Apache Tomcat) (8.0.0.0-8.2.4.0) Oracle Communications Applications / Pricing (Apache Tomcat) (12.0.0.3.0) Oracle Construction and Engineering / Core (Apache Tomcat) (17.1, 17.2, 17.3) Oracle MySQL / Monitoring: General (Apache Tomcat) (8.0.25 and prior) Oracle Virtualization / Core (Apache Tomcat) (5.6)

Advisory

Type

Quarter

Products Oracle names in its risk matrix

Oracle Critical Patch Update April 2025 ↗

CPU

2025-Q2

Oracle Autonomous Health Framework / Trace File Analyzer (Apache Tomcat) (23.8.0-23.11.0, 24.1.0-24.11.0, 25.1.0, 25.2.0)

Oracle Critical Patch Update April 2022 ↗

CPU

2022-Q2

Oracle Fusion Middleware / MFT Runtime Server (Apache Tomcat) (12.2.1.3.0, 12.2.1.4.0)
Oracle HealthCare Applications / Datastudio (Apache Tomcat) (4.1.0)

Oracle Critical Patch Update January 2022 ↗

CPU

2022-Q1

Oracle Communications / SCP (Apache Tomcat) (1.14.0)
Oracle Graph Server and Client / Packaging/Install (Apache Tomcat) (Prior to 21.4)
Oracle Supply Chain / Security (Apache Tomcat) (9.3.6)
Oracle Utilities Applications / Tools (Apache Tomcat) (6.0.0.1.1, 6.0.0.2.2, 6.0.0.3.1)

Oracle Critical Patch Update October 2021 ↗

CPU

2021-Q4

Oracle Communications / MediationServer (Apache Tomcat) (12.5.0)
Oracle Communications / Platform (Apache Tomcat) (8.0.0.0-8.5.0.0)
Oracle Communications / Reports (Apache Tomcat) (8.0.0.0-8.2.4.0)
Oracle Communications / Route Manager (Apache Tomcat) (8.0.0.0-8.2.4.0)
Oracle Communications Applications / Pricing (Apache Tomcat) (12.0.0.3.0)
Oracle Construction and Engineering / Core (Apache Tomcat) (17.1, 17.2, 17.3)
Oracle MySQL / Monitoring: General (Apache Tomcat) (8.0.25 and prior)
Oracle Virtualization / Core (Apache Tomcat) (5.6)

Oracle components and versions

Family	Component	Versions, as Oracle lists them	Read as
Oracle Autonomous Health Framework	Trace File Analyzer (Apache Tomcat)	23.8.0-23.11.0, 24.1.0-24.11.0, 25.1.0, 25.2.0	25.1.0 · 25.2.0
Oracle Communications	MediationServer (Apache Tomcat)	12.5.0	12.5.0
Oracle Communications	Platform (Apache Tomcat)	8.0.0.0-8.5.0.0
Oracle Communications	Reports (Apache Tomcat)	8.0.0.0-8.2.4.0
Oracle Communications	Route Manager (Apache Tomcat)	8.0.0.0-8.2.4.0
Oracle Communications	SCP (Apache Tomcat)	1.14.0	1.14.0
Oracle Communications Applications	Pricing (Apache Tomcat)	12.0.0.3.0	12.0.0.3.0
Oracle Construction and Engineering	Core (Apache Tomcat)	17.1, 17.2, 17.3	17.1 · 17.2 · 17.3
Oracle Fusion Middleware	MFT Runtime Server (Apache Tomcat)	12.2.1.3.0, 12.2.1.4.0	12.2.1.3.0 · 12.2.1.4.0
Oracle Graph Server and Client	Packaging/Install (Apache Tomcat)	Prior to 21.4
Oracle HealthCare Applications	Datastudio (Apache Tomcat)	4.1.0	4.1.0
Oracle MySQL	Monitoring: General (Apache Tomcat)	8.0.25 and prior
Oracle Supply Chain	Security (Apache Tomcat)	9.3.6	9.3.6
Oracle Utilities Applications	Tools (Apache Tomcat)	6.0.0.1.1, 6.0.0.2.2, 6.0.0.3.1	6.0.0.1.1 · 6.0.0.2.2 · 6.0.0.3.1
Oracle Virtualization	Core (Apache Tomcat)	5.6	5.6

Family

Component

Versions, as Oracle lists them

Read as

Oracle Autonomous Health Framework

Trace File Analyzer (Apache Tomcat)

23.8.0-23.11.0, 24.1.0-24.11.0, 25.1.0, 25.2.0

25.1.0 · 25.2.0

Oracle Communications

MediationServer (Apache Tomcat)

12.5.0

Oracle Communications

Platform (Apache Tomcat)

8.0.0.0-8.5.0.0

Oracle Communications

Reports (Apache Tomcat)

8.0.0.0-8.2.4.0

Oracle Communications

Route Manager (Apache Tomcat)

8.0.0.0-8.2.4.0

Oracle Communications

SCP (Apache Tomcat)

1.14.0

Oracle Communications Applications

Pricing (Apache Tomcat)

12.0.0.3.0

Oracle Construction and Engineering

Core (Apache Tomcat)

17.1, 17.2, 17.3

17.1 · 17.2 · 17.3

Oracle Fusion Middleware

MFT Runtime Server (Apache Tomcat)

12.2.1.3.0, 12.2.1.4.0

12.2.1.3.0 · 12.2.1.4.0

Oracle Graph Server and Client

Packaging/Install (Apache Tomcat)

Prior to 21.4

Oracle HealthCare Applications

Datastudio (Apache Tomcat)

4.1.0

Oracle MySQL

Monitoring: General (Apache Tomcat)

8.0.25 and prior

Oracle Supply Chain

Security (Apache Tomcat)

9.3.6

Oracle Utilities Applications

Tools (Apache Tomcat)

6.0.0.1.1, 6.0.0.2.2, 6.0.0.3.1

6.0.0.1.1 · 6.0.0.2.2 · 6.0.0.3.1

Oracle Virtualization

Core (Apache Tomcat)

5.6

Maven packages

Affected and fixed versions, from OSV.dev

Package Introduced Fixed Last affected

org.apache.tomcat:tomcat 10.0.0-M1 10.0.7 unbounded

org.apache.tomcat:tomcat 9.0.0-M1 9.0.48 unbounded

org.apache.tomcat:tomcat 8.5.0 8.5.68 unbounded

Package	Introduced	Fixed	Last affected
`org.apache.tomcat:tomcat`	10.0.0-M1	`10.0.7`	unbounded
`org.apache.tomcat:tomcat`	9.0.0-M1	`9.0.48`	unbounded
`org.apache.tomcat:tomcat`	8.5.0	`8.5.68`	unbounded

Products and versions

23 products, 45 version entries

Source	Vendor	Product	Scheme	Affected versions
nvd	apache	tomcat	generic	≥ 8.5.0 and ≤ 8.5.66 · ＞ 9.0.0 and ≤ 9.0.46 · ＞ 10.0.0 and ≤ 10.0.6
nvd	apache	tomee	generic	8.0.6
nvd	debian	debian linux	generic	9.0 · 10.0
nvd	mcafee	epolicy orchestrator	generic	5.10.0 · ＜ 5.10.0 · 5.10.0:update_1 · 5.10.0:update_2 · 5.10.0:update_3 · 5.10.0:update_4 · 5.10.0:update_5 · 5.10.0:update_6 · 5.10.0:update_7 · 5.10.0:update_8 · 5.10.0:update_9 · 5.10.0:update_10
nvd	oracle	agile product lifecycle management	generic	9.3.6
nvd	oracle	communications cloud native core policy	generic	1.14.0
nvd	oracle	communications cloud native core service communication proxy	generic	1.14.0
nvd	oracle	communications diameter signaling router	generic	≥ 8.0.0.0 and ≤ 8.5.0.2
nvd	oracle	communications instant messaging server	generic	10.0.1.5.0
nvd	oracle	communications policy management	generic	12.5.0
nvd	oracle	communications pricing design center	generic	12.0.0.3.0
nvd	oracle	communications session report manager	generic	≥ 8.0.0 and ≤ 8.2.4.0
nvd	oracle	communications session route manager	generic	≥ 8.0.0 and ≤ 8.2.4
nvd	oracle	graph server and client	generic	＜ 21.4
nvd	oracle	healthcare translational research	generic	4.1.0
nvd	oracle	hospitality cruise shipboard property management system	generic	20.1.0
nvd	oracle	instantis enterprisetrack	generic	17.1 · 17.2 · 17.3
nvd	oracle	managed file transfer	generic	12.2.1.3.0 · 12.2.1.4.0
nvd	oracle	mysql enterprise monitor	generic	≤ 8.0.25
nvd	oracle	sd-wan edge	generic	9.0 · 9.1
nvd	oracle	secure global desktop	generic	5.6
nvd	oracle	utilities testing accelerator	generic	6.0.0.1.1 · 6.0.0.2.2 · 6.0.0.3.1
osv	org.apache.tomcat	tomcat	generic	≥ 8.5.0 and ＜ 8.5.68 · ≥ 9.0.0 and ＜ 9.0.48 · ≥ 10.0.0 and ＜ 10.0.7

Source

Vendor

Product

Scheme

Affected versions

nvd

apache

tomcat

generic

≥ 8.5.0 and ≤ 8.5.66 · ＞ 9.0.0 and ≤ 9.0.46 · ＞ 10.0.0 and ≤ 10.0.6

nvd

apache

tomee

generic

8.0.6

nvd

debian

debian linux

generic

9.0 · 10.0

nvd

mcafee

epolicy orchestrator

generic

5.10.0 · ＜ 5.10.0 · 5.10.0:update_1 · 5.10.0:update_2 · 5.10.0:update_3 · 5.10.0:update_4 · 5.10.0:update_5 · 5.10.0:update_6 · 5.10.0:update_7 · 5.10.0:update_8 · 5.10.0:update_9 · 5.10.0:update_10

nvd

oracle

agile product lifecycle management

generic

9.3.6

nvd

oracle

communications cloud native core policy

generic

1.14.0

nvd

oracle

communications cloud native core service communication proxy

generic

1.14.0

nvd

oracle

communications diameter signaling router

generic

≥ 8.0.0.0 and ≤ 8.5.0.2

nvd

oracle

communications instant messaging server

generic

10.0.1.5.0

nvd

oracle

communications policy management

generic

12.5.0

nvd

oracle

communications pricing design center

generic

12.0.0.3.0

nvd

oracle

communications session report manager

generic

≥ 8.0.0 and ≤ 8.2.4.0

nvd

oracle

communications session route manager

generic

≥ 8.0.0 and ≤ 8.2.4

nvd

oracle

graph server and client

generic

＜ 21.4

nvd

oracle

healthcare translational research

generic

4.1.0

nvd

oracle

hospitality cruise shipboard property management system

generic

20.1.0

nvd

oracle

instantis enterprisetrack

generic

17.1 · 17.2 · 17.3

nvd

oracle

managed file transfer

generic

12.2.1.3.0 · 12.2.1.4.0

nvd

oracle

mysql enterprise monitor

generic

≤ 8.0.25

nvd

oracle

sd-wan edge

generic

9.0 · 9.1

nvd

oracle

secure global desktop

generic

5.6

nvd

oracle

utilities testing accelerator

generic

6.0.0.1.1 · 6.0.0.2.2 · 6.0.0.3.1

osv

org.apache.tomcat

tomcat

generic

≥ 8.5.0 and ＜ 8.5.68 · ≥ 9.0.0 and ＜ 9.0.48 · ≥ 10.0.0 and ＜ 10.0.7

Earlier manual review

A reviewer classified this CVE in an older dataset. We kept the labels and products below, but not the reviewer's reasoning.

## Manual Classification Context **Labels:** HTTP, ROUTE MANAGER (APACHE TOMCAT), PLATFORM (APACHE TOMCAT), NO AUTH REMOTE EXPLOIT, MEDIATIONSERVER (APACHE TOMCAT), PACKAGING/INSTALL (APACHE TOMCAT), SCP (APACHE TOMCAT), TOOLS (APACHE TOMCAT), PRICING (APACHE TOMCAT), CORE (APACHE TOMCAT), MONITORING: GENERAL (APACHE TOMCAT), SECURITY (APACHE TOMCAT), REPORTS (APACHE TOMCAT), APACHE JSERV PROTOCOL (AJP) **Products:** ORACLE COMMUNICATIONS SESSION ROUTE MANAGER, ORACLE VIRTUALIZATION, ORACLE COMMUNICATIONS CLOUD NATIVE CORE SERVICE COMMUNICATION PROXY, MYSQL ENTERPRISE MONITOR, ORACLE COMMUNICATIONS DIAMETER SIGNALING ROUTER, ORACLE COMMUNICATIONS, ORACLE MYSQL, INSTANTIS ENTERPRISETRACK, ORACLE SECURE GLOBAL DESKTOP, ORACLE SUPPLY CHAIN, ORACLE AGILE PLM, ORACLE GRAPH SERVER AND CLIENT, ORACLE COMMUNICATIONS PRICING DESIGN CENTER, ORACLE CONSTRUCTION AND ENGINEERING, ORACLE UTILITIES TESTING ACCELERATOR, ORACLE COMMUNICATIONS APPLICATIONS, ORACLE UTILITIES APPLICATIONS, ORACLE COMMUNICATIONS SESSION REPORT MANAGER, ORACLE COMMUNICATIONS POLICY MANAGEMENT

References

URL	Tags
https://github.com/apache/tomcat/commit/05f9e8b00f5d9251fcd3c95dcfd6cf84177f46c8	WEB
https://github.com/apache/tomcat/commit/19d11556d0db99df291df33605f137976d152475	WEB
https://github.com/apache/tomcat/commit/3202703e6d635e39b74262e81f0cb4bcbe2170dc	WEB
https://github.com/apache/tomcat/commit/45d70a86a901cbd534f8f570bed2aec9f7f7b88e	WEB
https://github.com/apache/tomcat/commit/506134f957a4be2c5b4a9334f7b3435fc954dbc1	WEB
https://github.com/apache/tomcat/commit/8874fa02e9b36baa9ca6b226c0882c0190ca5a02	WEB
https://github.com/apache/tomcat/commit/a2c3dc4c96168743ac0bab613709a5bbdaec41d0	WEB
https://github.com/apache/tomcat/commit/da0e7cb093cf68b052d9175e469dbd0464441b0b	WEB
https://github.com/apache/tomcat/commit/eee0d024c1b3171560c92eaba79dd6eb8eb11bcd	WEB
https://security.gentoo.org/glsa/202208-34	WEB

URL

Timeline

Published	2021-07-12	By the CVE Program.
NVD record modified	2026-10-08	NVD's own last-modified date for this record.

Published

2021-07-12

By the CVE Program.

NVD record modified

2026-10-08

NVD's own last-modified date for this record.

How VRT decided (5 of 24 rules ran)

5 of 24 rules ran. The rest didn't run because an earlier rule had already settled the CVE.

# Rule Outcome Status Detail

identity: Does this identifier describe a vulnerability at all? the first rule that matches decides

1 rejected no match CVE Program withdrawal of this identifier

scope: Is it a vulnerability Waratek protects? the first rule that matches decides

2 armr-patch-file no match An ARMR patch file on disk for this CVE

3 armr-secure-rule-file no match An ARMR security-rule template on disk for this CVE

4 manual-classification no match A researcher's recorded decision for this specific CVE

5 manual classification decided it matched No exploit published Found in legacy manual classifications

6 non-java-upstream not reached A root cause in non-Java code: an OS kernel, a C library, or a bundled runtime

7 oracle-component not reached The defect being in a component of a tracked product the agent does not reach: JavaFX, the Java SE installer, the JInitiator browser plug-in, the native WebLogic proxy plug-in, or a native part of Oracle Application Server or Collaboration Suite (HTTP Server, Web Cache, Internet Directory, mail and calendar servers). Oracle gives these no CPE of their own and names them only in the description.

8 java-client-side not reached Oracle's own risk-matrix note saying the CVE is reached only through untrusted code in the Java sandbox (applets, Web Start) or only through a client installation of Java, so a server running its own trusted code is not exposed

9 osv-maven not reached An OSV.dev record of this CVE affecting a package published to Maven Central. When every such package is one business applications do not use (Minecraft mods and launchers, Fastjson) and no tracked product is named by CPE, it settles the CVE as Outside Waratek scope instead

10 cna-maven-package not reached An affected Maven artifact named by the CNA itself

11 known-cpe-product not reached An NVD CPE naming a product ARMR tracks

12 cna-cpe-product not reached A CPE the CNA published naming a tracked product. Oracle publishes these on advisory day, months before NVD.

13 oracle-advisory-family not reached A tracked product family named in Oracle's own risk matrix. CPE cannot carry a suite name, only a module.

14 cna-named-product not reached A tracked product named in words by the CVE's own CNA, on a record with no CPE yet. Apache and Eclipse publish these on advisory day, before NVD adds CPE data.

15 non-deployable-product not reached The only affected product being a sealed appliance image, where Java runs but no -javaagent can be attached

16 unmatched-product not reached No tracked product matched above, and none present at all

disposition: What do we do about one that is? every rule runs

17 patch-hint not reached A reference pointing at the upstream fix: a commit, a PR, a Red Hat bug

18 open-source-maven not reached The affected package being open source on Maven, so the fix can be read

19 poc-derivable not reached An indexed exploit clearing the evidence bar to reverse-engineer, where there is no source to read

20 no-exploit not reached Nothing to build a rule from yet: no published exploit, no CISA record of exploitation and no source-level change to read

21 secure-rule-match not reached A vulnerability class already blocked by an ARMR security rule

22 exploited-no-fix-or-poc not reached Somebody exploiting this CVE (a CISA or VulnCheck KEV listing, or a CISA verdict of active exploitation), with no fix, source code or PoC to build a rule from

23 below-action-threshold not reached Medium or Low severity, no CISA or VulnCheck KEV listing, no PoC clearing the evidence bar, no CISA verdict, no Oracle advisory

24 no-exploit-published not reached Exploit code for this candidate, published in a reviewed catalogue or a GitHub repository with 5 or more stars, or in use per CISA or VulnCheck; not only a CISA verdict, a forecast, or nothing at all

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