CVE-2021-33037EPSS p99.5%
CVE-2021-33037CVE-2021-33037
apache / tomcat
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.
Scoring
| CVSS | 5.3 () |
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N |
| EPSS | 74.67% probability of exploitation · percentile 99.5% · 2026-10-05T12:00:23Z |
| Last modified | 2026-08-25 |