Improper Encoding or Escaping of Output Affecting tomcat9 package, versions <9.0.43-2


Severity

Recommended
0.0
medium
0
10

Snyk's Security Team recommends NVD's CVSS assessment. Learn more

Threat Intelligence

EPSS
9.89% (95th percentile)

Do your applications use this vulnerable package?

In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.

Test your applications
  • Snyk IDSNYK-ECHOLATEST-TOMCAT9-18001059
  • published17 Jul 2026
  • disclosed12 Jul 2021

Introduced: 12 Jul 2021

CVE-2021-30640  (opens in a new tab)
CWE-116  (opens in a new tab)

How to fix?

Upgrade Echo:latest tomcat9 to version 9.0.43-2 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream tomcat9 package and not the tomcat9 package as distributed by Echo. See How to fix? for Echo:latest relevant fixed versions and status.

A vulnerability in the JNDI Realm of Apache Tomcat allows an attacker to authenticate using variations of a valid user name and/or to bypass some of the protection provided by the LockOut Realm. This issue affects Apache Tomcat 10.0.0-M1 to 10.0.5; 9.0.0.M1 to 9.0.45; 8.5.0 to 8.5.65.

CVSS Base Scores

version 3.1