CVE-2026-77756 (GCVE-0-2026-77756)

Vulnerability from cvelistv5 – Published: 2026-09-23 11:18 – Updated: 2026-09-23 18:10
VLAI
Title
Apache Tomcat: Transfer-Encoding honored for HTTP/1.0 requests
Summary
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.
Severity
3.7 (Low)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-23 13:18 UTC
CWE
  • CWE-444 - Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')
Assigner
apache CNA under the mitre root
CNA scorecard B 76/100 over 1090 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Apache Software Foundation Apache Tomcat Affected: 11.0.0-M1 , ≤ 11.0.25 (semver)
Affected: 10.1.0-M1 , ≤ 10.1.59 (semver)
Affected: 9.0.47 , ≤ 9.0.121 (semver)
Affected: 8.5.67 , ≤ 8.5.100 (semver)
Unaffected: 0 , ≤ 7.0.109 (semver)
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