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CVE-2021-33037

Incorrect Transfer-Encoding handling with HTTP/1.0

Published: Jul 12, 2021Updated: Nov 21, 2024 Sources: CVE List NVD GHSA BDUCWE-444
NVD MITRE
5.3CVSSMEDIUM
EPSS Score
75.4%
Top 0.5%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Am I actually vulnerable?1 Nuclei template available — see how to check your systems. How to verify

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.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:NI:LA:N
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:LIntegrity
Low
A:NAvailability
None
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Weaknesses

CWE-444

Affected Products

Red Hat JBoss FuseRed Hat Inc.
On-premOS
Operating Systems / linux-distro
Jboss Web ServerRed Hat Inc.
On-premWeb App
Web & CMS Plugins
РЕД ОСООО «Ред Софт»
On-premOS
Operating Systems / linux-distro
OpenShift Application RuntimesRed Hat Inc.
MixedSaaS Service
Cloud & SaaS / cloud-platform
TomcatApache Software Foundation
On-premWeb App
Networking Infrastructure / load-balancer-proxy
red hat inc.commercialUSOperating Systemsaka red hat
ооо «ред софт»commercialRUOperating Systemsaka red soft
apache software foundationoss-projectUSWeb & CMS Pluginsaka apache foundation
and 29 more affected products View all →

Attack Graph

Products CVE Techniques Tactics

Click technique nodes to view MITRE ATT&CK details. Scroll to zoom, drag to pan.

Exploitability

Official Patch Available

MITRE ATT&CK

1 technique
Collection
View detailed technique mapping

References

https://lists.apache.org/thread.html/r612a79269b0d5e5780c62dfd34286a8037232fec0bc6f1a7e60c9381%40%3Cannounce.tomcat.apache.org%3E
lists.apache.org
https://nvd.nist.gov/vuln/detail/CVE-2021-33037
nvd.nist.gov
https://access.redhat.com/security/cve/cve-2021-33037
access.redhat.com
and 44 more references View all →

Timeline

Published
Jul 12, 2021
Last Updated
Nov 21, 2024

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