Vulnerability in Apache Software Foundation Tomcat

CVE-2021-33037

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 prox…

Vulnerability class: HTTP Request Smuggling

EPSS: 0.754 (99.5th percentile) — read the EPSS interpretation.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2021-33037?
CVE-2021-33037 is a vulnerability in Apache Software Foundation Tomcat, classified under Inconsistent Interpretation of HTTP Requests (HTTP Request/Response Smuggling). Published 2021-07-12.
Is CVE-2021-33037 known to be exploited?
6 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.