GHSA-fv25-8xcx-gqjc BIT-tomcat-2026-42498 CVE-2026-42498
Apache Tomcat - WebSocket authentication header exposure
- Severity
- 7.3 / 10
- High · CVSS 3.1
- Exploit chance (EPSS)
- 0.65%
- Chance of exploitation in the next 30 days. Higher than 50.96% of scored vulnerabilities.
- Known exploited
- No
- Not in CISA's catalog
- Weakness
- CWE-200 Exposure of Sensitive Information to an Unauthorized Actor
- Fix
- Available
- 3 packages have a fixed version
Description
Versions Affected: Apache Tomcat 11.0.0-M1 to 11.0.21 Apache Tomcat 10.1.0-M1 to 10.1.54 Apache Tomcat 9.0.2 to 9.0.117 Older, unsupported versions may also be affected
Description: If a WebSocket request was redirected after authentication, Tomcat's WebSocket client would present the most recent authentication header to the redirect target host.
Mitigation: Users of the affected versions should apply one of the following mitigations:
- Upgrade to Apache Tomcat 11.0.22 or later
- Upgrade to Apache Tomcat 10.1.55 or later
- Upgrade to Apache Tomcat 9.0.118 or later
Credit: This issue was identified by lokerxx
Affected versions
Maven
| Package | Vulnerable | Fixed in |
|---|---|---|
| org.apache.tomcat.embed:tomcat-embed-core | < 9.0.118 |
9.0.118 |
| org.apache.tomcat.embed:tomcat-embed-core | >= 10.1.0-M1, < 10.1.55 |
10.1.55 |
| org.apache.tomcat.embed:tomcat-embed-core | >= 11.0.0-M1, < 11.0.22 |
11.0.22 |
| org.apache.tomcat:tomcat | < 9.0.118 |
9.0.118 |
| org.apache.tomcat:tomcat | >= 10.1.0-M1, < 10.1.55 |
10.1.55 |
| org.apache.tomcat:tomcat | >= 11.0.0-M1, < 11.0.22 |
11.0.22 |
| org.apache.tomcat:tomcat-catalina | < 9.0.118 |
9.0.118 |
| org.apache.tomcat:tomcat-catalina | >= 10.1.0-M1, < 10.1.55 |
10.1.55 |
| org.apache.tomcat:tomcat-catalina | >= 11.0.0-M1, < 11.0.22 |
11.0.22 |
How to fix
Move to the fixed version or later with your package manager, update the lockfile, and run your tests. If the package only arrives through another dependency, upgrade that dependency first. If none of its releases pulls a fixed version yet, force the version with your package manager's override.
org.apache.tomcat.embed:tomcat-embed-core Maven → 9.0.118
- maven
<dependency><groupId>org.apache.tomcat.embed</groupId><artifactId>tomcat-embed-core</artifactId><version>9.0.118</version></dependency>- gradle
implementation("org.apache.tomcat.embed:tomcat-embed-core:9.0.118")
org.apache.tomcat:tomcat Maven → 9.0.118
- maven
<dependency><groupId>org.apache.tomcat</groupId><artifactId>tomcat</artifactId><version>9.0.118</version></dependency>- gradle
implementation("org.apache.tomcat:tomcat:9.0.118")
org.apache.tomcat:tomcat-catalina Maven → 9.0.118
- maven
<dependency><groupId>org.apache.tomcat</groupId><artifactId>tomcat-catalina</artifactId><version>9.0.118</version></dependency>- gradle
implementation("org.apache.tomcat:tomcat-catalina:9.0.118")
Severity breakdown
CVSS 3.1 7.3
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- Low
- Integrity
- Low
- Availability
- Low
Weakness
CWE-200: Exposure of Sensitive Information to an Unauthorized Actor
The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.
How to prevent it
- Architecture and Design: Compartmentalize the system to have "safe" areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area. Ensure that appropriate compartmentalization is built into the system design, and the compartmentalization allows for and reinforces privilege separation functionality. Architects and designers should rely on the principle of least privilege to decide the appropriate time to use privileges and the time to drop privileges.
References
Advisories
Packages
Other links
- github.com/apache/tomcat/commit/169d725788ea6aec217ecac70fe4161c837ba423
- github.com/apache/tomcat/commit/6cbe274592ef2d11607b5b188e1df649de52f8d5
- github.com/apache/tomcat/commit/b7b173694d588ddcfa432f079baf763cbbbaa5c4
- lists.apache.org/thread/n61zwf75jrv09rz90j4jssncm244bwdb
- tomcat.apache.org/security-10.html
- tomcat.apache.org/security-11.html
- tomcat.apache.org/security-9.html
- openwall.com/lists/oss-security/2026/05/12/14
Timeline
- Published
- Last updated by the source
- Latest EPSS score
Related advisories
| Advisory | Severity | Why it's related |
|---|---|---|
| GHSA-69r9-qgr7-g2wj Apache Tomcat Missing Encryption of Sensitive Data vulnerability | High Known exploited | Also affects org.apache.tomcat:tomcat |
| GHSA-83qj-6fr2-vhqg Apache Tomcat: Potential RCE and/or information disclosure and/or information corruption with partial PUT | Critical Known exploited | Also affects org.apache.tomcat.embed:tomcat-embed-core |
| GHSA-qppj-fm5r-hxr3 HTTP/2 Stream Cancellation Attack | Medium Known exploited | Also affects org.apache.tomcat.embed:tomcat-embed-core |
| GHSA-xjgh-84hx-56c5 Unrestricted Upload of File with Dangerous Type Apache Tomcat | High Known exploited | Also affects org.apache.tomcat.embed:tomcat-embed-core |
| GHSA-cw54-59pw-4g8c Apache Tomcat Improper Access Control vulnerability | Critical Known exploited | Also affects org.apache.tomcat:tomcat-catalina |
| CVE-2020-1938 Improper Privilege Management in Tomcat | Critical Known exploited | Also affects org.apache.tomcat.embed:tomcat-embed-core |
| GHSA-pjfr-qf3p-3q25 When running Apache Tomcat on Windows with HTTP PUTs enabled it was possible to upload a JSP file to the server | High Known exploited | Also affects org.apache.tomcat.embed:tomcat-embed-core |
| GHSA-h3x4-894j-xpx5 Apache Tomcat's FORM authentication process has an Incorrect Authorization vulnerability | Critical | Also affects org.apache.tomcat.embed:tomcat-embed-core |
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