CVE-2026-55276
Apache Tomcat: Logged effective web.xml is incomplete
Description
Always-Incorrect Control Flow Implementation vulnerability in Apache Tomcat meant that special roles and empty authorisation constraints were not included when the effective web.xml was logged. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.22, from 10.1.0-M1 through 10.1.55, from 9.0.0.M1 through 9.0.118, from 8.5.0 through 8.5.100. Other versions that have reached end of support may also be affected. Users are recommended to upgrade to version 11.0.23, 10.1.56 or 9.0.119 which fixes the issue.
INFO
Published Date :
June 29, 2026, 9:16 p.m.
Last Modified :
July 2, 2026, 7:05 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | CRITICAL | 134c704f-9b21-4f2e-91b3-4a467353bcc0 |
Solution
- Upgrade Tomcat to version 11.0.23 or later.
- Upgrade Tomcat to version 10.1.56 or later.
- Upgrade Tomcat to version 9.0.119 or later.
Public PoC/Exploit Available at Github
CVE-2026-55276 has a 1 public
PoC/Exploit available at Github.
Go to the Public Exploits tab to see the list.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-55276.
| URL | Resource |
|---|---|
| https://lists.apache.org/thread/jy09xjlzn6r2qwvqoph8vcmf959yq68v | Vendor Advisory Mailing List |
| http://www.openwall.com/lists/oss-security/2026/06/29/23 | Third Party Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-55276 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-55276
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
None
Java Dockerfile
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-55276 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-55276 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
Jul. 02, 2026
Action Type Old Value New Value Added CPE Configuration OR *cpe:2.3:a:apache:tomcat:*:*:*:*:*:*:*:* versions from (including) 10.1.0 up to (excluding) 10.1.56 *cpe:2.3:a:apache:tomcat:*:*:*:*:*:*:*:* versions from (including) 11.0.0 up to (excluding) 11.0.23 *cpe:2.3:a:apache:tomcat:*:*:*:*:*:*:*:* versions up to (excluding) 9.0.119 Added Reference Type Apache Software Foundation: https://lists.apache.org/thread/jy09xjlzn6r2qwvqoph8vcmf959yq68v Types: Mailing List, Vendor Advisory Added Reference Type CVE: http://www.openwall.com/lists/oss-security/2026/06/29/23 Types: Third Party Advisory -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 30, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N Added SSVC {'id': 'CVE-2026-55276', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-06-30T13:59:26.729885Z'} -
CVE Modified by af854a3a-2127-422b-91ae-364da2661108
Jun. 29, 2026
Action Type Old Value New Value Added Reference http://www.openwall.com/lists/oss-security/2026/06/29/23 -
New CVE Received by [email protected]
Jun. 29, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'Apache Software Foundation', 'product': 'Apache Tomcat', 'versions': [{'status': 'affected', 'version': '11.0.0-M1', 'versionType': 'semver', 'lessThanOrEqual': '11.0.22'}, {'status': 'affected', 'version': '10.1.0-M1', 'versionType': 'semver', 'lessThanOrEqual': '10.1.55'}, {'status': 'affected', 'version': '9.0.0.M1', 'versionType': 'semver', 'lessThanOrEqual': '9.0.118'}, {'status': 'affected', 'version': '8.5.0', 'versionType': 'semver', 'lessThanOrEqual': '8.5.100'}, {'status': 'unaffected', 'version': '0', 'lessThan': '8.0.0', 'versionType': 'semver'}], 'defaultStatus': 'unaffected'}] Added Description Always-Incorrect Control Flow Implementation vulnerability in Apache Tomcat meant that special roles and empty authorisation constraints were not included when the effective web.xml was logged. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.22, from 10.1.0-M1 through 10.1.55, from 9.0.0.M1 through 9.0.118, from 8.5.0 through 8.5.100. Other versions that have reached end of support may also be affected. Users are recommended to upgrade to version 11.0.23, 10.1.56 or 9.0.119 which fixes the issue. Added CWE CWE-670 Added Reference https://lists.apache.org/thread/jy09xjlzn6r2qwvqoph8vcmf959yq68v