Apache Tomcat up to 11.0.21 authentication bypass issues

Summaryinfo

A vulnerability was found in Apache Tomcat up to 7.0.109/8.5.100/9.0.117/10.1.54/11.0.21. It has been rated as critical. This vulnerability affects unknown code. Performing a manipulation results in authentication bypass issues. This vulnerability is cataloged as CVE-2026-43512. It is possible to initiate the attack remotely. There is no exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability classified as critical has been found in Apache Tomcat up to 7.0.109/8.5.100/9.0.117/10.1.54/11.0.21. This affects an unknown function. The manipulation with an unknown input leads to a authentication bypass issues vulnerability. CWE is classifying the issue as CWE-592. This weakness has been deprecated because it covered redundant concepts already described in CWE-287. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

DEPRECATED: Authentication Bypass Issues vulnerability in digest authentication in Apache Tomcat. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.21, from 10.1.0-M1 through 10.1.54, from 9.0.0.M1 through 9.0.117, from 8.5.0 through 8.5.100, from before 7.0.0. Older unsupported versions any also be affect Users are recommended to upgrade to version 11.0.22, 10.1.55 or 9.0.118 which fix the issue.

The advisory is shared at lists.apache.org. This vulnerability is uniquely identified as CVE-2026-43512 since 05/01/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 07/29/2026).

The vulnerability scanner Nessus provides a plugin with the ID 314335 (Apache Tomcat 10.1.0.M1 < 10.1.55 multiple vulnerabilities), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 9.0.118, 10.1.55 or 11.0.22 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (314335) and CERT Bund (WID-SEC-2026-2308). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Affected

• SAP Software

Productinfo

Type

• Application Server Software

Vendor

• Apache

Name

• Tomcat

Version

• 7.0.109
• 8.0
• 8.1
• 8.2
• 8.3
• 8.4
• 8.5.100
• 9.0.117
• 10.1.0
• 10.1.1
• 10.1.2
• 10.1.3
• 10.1.4
• 10.1.5
• 10.1.6
• 10.1.7
• 10.1.8
• 10.1.9
• 10.1.10
• 10.1.11
• 10.1.12
• 10.1.13
• 10.1.14
• 10.1.15
• 10.1.16
• 10.1.17
• 10.1.18
• 10.1.19
• 10.1.20
• 10.1.21
• 10.1.22
• 10.1.23
• 10.1.24
• 10.1.25
• 10.1.26
• 10.1.27
• 10.1.28
• 10.1.29
• 10.1.30
• 10.1.31
• 10.1.32
• 10.1.33
• 10.1.34
• 10.1.35
• 10.1.36
• 10.1.37
• 10.1.38
• 10.1.39
• 10.1.40
• 10.1.41
• 10.1.42
• 10.1.43
• 10.1.44
• 10.1.45
• 10.1.46
• 10.1.47
• 10.1.48
• 10.1.49
• 10.1.50
• 10.1.51
• 10.1.52
• 10.1.53
• 10.1.54
• 11.0.0
• 11.0.1
• 11.0.2
• 11.0.3
• 11.0.4
• 11.0.5
• 11.0.6
• 11.0.7
• 11.0.8
• 11.0.9
• 11.0.10
• 11.0.11
• 11.0.12
• 11.0.13
• 11.0.14
• 11.0.15
• 11.0.16
• 11.0.17
• 11.0.18
• 11.0.19
• 11.0.20
• 11.0.21

License

• open-source

Website

• Vendor: https://www.apache.org/

CPE 2.3info

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CPE 2.2info

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Threat Intelligenceinfo

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Sourcesinfo

Entryinfo

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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