CVE-2026-87022: CWE-130 Improper handling of length parameter inconsistency in Apache Software Foundation Apache Tomcat
Improper handling of length parameter inconsistency vulnerability in Apache Tomcat allows WebSocket message smuggling when per-message-deflate is used. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.25, from 10.1.0-M1 through 10.1.59, from 9.0.0.M1 through 9.0.121. The following versions were EOS at the time the CVE was created but are known to be affected: from 8.5.0 through 8.5.100, from 7.0.56 through 7.0.109. Other unsupported versions may also be affected. Users are recommended to upgrade to version 11.0.26, 10.1.60 or 9.1.22, which fix the issue.
AI Analysis
Technical Summary
The vulnerability identified as CVE-2026-87022 in Apache Tomcat is due to improper handling of length parameter inconsistencies in WebSocket frames when the per-message-deflate extension is enabled. This flaw allows an attacker to perform WebSocket message smuggling, potentially interfering with message boundaries and processing. Affected versions span multiple major releases of Apache Tomcat, including some end-of-support versions. The Apache Software Foundation has released fixed versions 11.0.26, 10.1.60, and 9.1.22 to address this issue.
Potential Impact
The vulnerability allows WebSocket message smuggling when per-message-deflate is used, which can disrupt normal WebSocket communication. The exact impact beyond message smuggling is not detailed in the provided data. No known exploits in the wild have been reported at the time of publication.
Mitigation Recommendations
Users should upgrade affected Apache Tomcat versions to 11.0.26, 10.1.60, or 9.1.22, which contain fixes for this vulnerability. No other mitigation or temporary workaround is indicated in the available information.
CVE-2026-87022: CWE-130 Improper handling of length parameter inconsistency in Apache Software Foundation Apache Tomcat
Description
Improper handling of length parameter inconsistency vulnerability in Apache Tomcat allows WebSocket message smuggling when per-message-deflate is used. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.25, from 10.1.0-M1 through 10.1.59, from 9.0.0.M1 through 9.0.121. The following versions were EOS at the time the CVE was created but are known to be affected: from 8.5.0 through 8.5.100, from 7.0.56 through 7.0.109. Other unsupported versions may also be affected. Users are recommended to upgrade to version 11.0.26, 10.1.60 or 9.1.22, which fix the issue.
CVSS v3.1
Score 7.5high
Affected software
Apache Software Foundation
Apache Tomcat
pkg:maven/org.apache.tomcat/tomcatRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability identified as CVE-2026-87022 in Apache Tomcat is due to improper handling of length parameter inconsistencies in WebSocket frames when the per-message-deflate extension is enabled. This flaw allows an attacker to perform WebSocket message smuggling, potentially interfering with message boundaries and processing. Affected versions span multiple major releases of Apache Tomcat, including some end-of-support versions. The Apache Software Foundation has released fixed versions 11.0.26, 10.1.60, and 9.1.22 to address this issue.
Potential Impact
The vulnerability allows WebSocket message smuggling when per-message-deflate is used, which can disrupt normal WebSocket communication. The exact impact beyond message smuggling is not detailed in the provided data. No known exploits in the wild have been reported at the time of publication.
Mitigation Recommendations
Users should upgrade affected Apache Tomcat versions to 11.0.26, 10.1.60, or 9.1.22, which contain fixes for this vulnerability. No other mitigation or temporary workaround is indicated in the available information.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- apache
- Date Reserved
- 2026-09-08T17:16:33.368Z
- State
- PUBLISHED
Threat ID: 6ab3bc94f7a7c54106b7b02b
Added to database: 09/23/2026, 11:48:36 UTC
Last enriched: 09/23/2026, 12:02:51 UTC
Last updated: 09/24/2026, 01:58:10 UTC
Views: 12
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