CVE-2026-77756
Public on 2026-09-23
Modified on 2026-09-25
Description
Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling') vulnerability in Apache Tomcat caused by processing the transfer-encoding header for an HTTP/1.0 request may allow an attacker to cause one request from another user to fail when Tomcat is located behind a reverse proxy.
This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.25, from 10.1.0-M1 through 10.1.59, from 9.0.47 through 9.0.121.
The following versions were EOL at the time the CVE was created but are known to be affected: from 8.5.67 through 8.5.100. Other unsupported versions may also be affected.
Users are recommended to upgrade to version 11.0.26, 10.1.60 or 9.0.122, which fix the issue.
This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.25, from 10.1.0-M1 through 10.1.59, from 9.0.47 through 9.0.121.
The following versions were EOL at the time the CVE was created but are known to be affected: from 8.5.67 through 8.5.100. Other unsupported versions may also be affected.
Users are recommended to upgrade to version 11.0.26, 10.1.60 or 9.0.122, which fix the issue.
CVSS v3 Base Score
See breakdown
Affected Packages
| Platform | Package | Release Date | Advisory | Status |
|---|---|---|---|---|
| Amazon Linux 2 - Tomcat9 Extra | tomcat | Pending Fix | ||
| Amazon Linux 2 - Core | tomcat | Not Affected | ||
| Amazon Linux 2 - Tomcat8.5 Extra | tomcat | No Fix Planned | ||
| Amazon Linux 2023 | tomcat10 | Pending Fix | ||
| Amazon Linux 2027 Preview | tomcat10 | Pending Fix | ||
| Amazon Linux 2023 | tomcat11 | Pending Fix | ||
| Amazon Linux 2023 | tomcat9 | Pending Fix | ||
| Amazon Linux 2027 Preview | tomcat9 | Pending Fix |
CVSS Scores
| Score Type | Score | Vector | |
|---|---|---|---|
| Amazon Linux | CVSSv3 | 4.8 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:L |