Authentication Bypass by Alternate Name in Apache Tomcat
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.
Affected software
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| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| Java / Kotlin (Maven) | org.apache.tomcat:tomcat | >= 10.0.0-M1, < 10.0.5, >= 9.0.0M1, < 9.0.45, >= 8.5.0, < 8.5.65 | 10.0.5, 9.0.45, 8.5.65 |
References
- https://nvd.nist.gov/vuln/detail/CVE-2021-30640
- https://lists.apache.org/thread.html/r59f9ef03929d32120f91f4ea7e6e79edd5688d75d0a9b65fd26d1fe8%40%3Cannounce.tomcat.apache.org%3E
- https://lists.debian.org/debian-lts-announce/2021/08/msg00009.html
- https://security.gentoo.org/glsa/202208-34
- https://security.netapp.com/advisory/ntap-20210827-0007
- https://www.debian.org/security/2021/dsa-4952
- https://www.debian.org/security/2021/dsa-4986
- https://www.oracle.com//security-alerts/cpujul2021.html
- https://www.oracle.com/security-alerts/cpujan2022.html
- https://www.oracle.com/security-alerts/cpuoct2021.html
- CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:N- Weakness (CWE)
CWE-116, CWE-287, CWE-289- Platform
- Java / Kotlin (Maven)
- Package
org.apache.tomcat:tomcat- Disclosed
- 13.08.2021
- Updated
- 11.10.2026 11:22
Sources and licenses
OSV / GitHub Advisory Database - GHSA-36qh-35cm-5w2w - CC BY 4.0
Vulnerability history: org.apache.tomcat:tomcat
All published vulnerabilities of this package (Java / Kotlin (Maven)), newest first. Shows whether this is a one-off slip or a package that needs watching.
- Total entries
- 162
- First → latest
- 12.2018 08.2026
- Without a fix
- 20
- Exploited in attacks
- 1
Severity breakdown
- Critical 8
- High 40
- Medium 102
- Low 12
Disclosures per year
- 2018: 1
- 2019: 1
- 2020: 2
- 2021: 5
- 2022: 125
- 2023: 3
- 2024: 2
- 2025: 4
- 2026: 19
-
Authentication Bypass by Alternate Name in Apache Tomcat this entry
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