CVE-2026-77762

high

Description

Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') vulnerability in Apache Tomcat allows an attacker to inject trailer fields into another HTTP/2 request. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.25, from 10.1.0-M1 through 10.1.59, from 9.0.39 through 9.0.121. The following versions were EOL at the time the CVE was created but are known to be affected: from 8.5.59 through 8.5.100. Other unsupported versions may also be affected. Users are recommended to upgrade to version 11.0.26, 10.1.60, 9.0.122, which fix the issue.

References

https://lists.apache.org/thread/y5r9fvjo7ol24mkoyoc0st8bqrfyqcyn

http://www.openwall.com/lists/oss-security/2026/09/23/23

Details

Source: Mitre, NVD

Published: 2026-09-23

Updated: 2026-09-23

Risk Information

CVSS v2

Base Score: 7.8

Vector: CVSS2#AV:N/AC:M/Au:N/C:C/I:P/A:N

Severity: High

CVSS v3

Base Score: 8.1

Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H