Stack-based buffer overflow in Apache Traffic Server - CVE-2026-33930

Vulnerability identifier: #VU144900

CSH Severity: Medium

CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-33930

CWE-ID: CWE-121

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to stack-based buffer overflow in redirect handling when copying a client Host header into a fixed-size stack buffer. A remote attacker can send an over-long Host header to cause a denial of service.

The issue is triggered when redirect following is enabled.

Apache Traffic Server
Fedora
openEuler
trafficserver
trafficserver-perl
trafficserver-devel
trafficserver-debugsource
trafficserver-debuginfo

Install security update from vendor's website.

Apache Traffic Server - addressed in versions 9.2.15, 10.1.4
trafficserver - update to 9.2.15-1
trafficserver-perl - update to 9.2.15-1
trafficserver-devel - update to 9.2.15-1
trafficserver-debugsource - update to 9.2.15-1
trafficserver-debuginfo - update to 9.2.15-1
trafficserver - addressed in versions 9.2.15-1.el8, 9.2.15-1.el9, 10.1.4-1.fc43, 10.1.4-1.fc44

• https://lists.apache.org/api/email.lua?id=5prl9glcm9g2swnq9hqxvnokylm1gr6d

• Multiple vulnerabilities in Apache Traffic Server
• Fedora EPEL 8 update for trafficserver
• Fedora EPEL 9 update for trafficserver
• Fedora 44 update for trafficserver
• Fedora 43 update for trafficserver
• openEuler 24.03 LTS SP1 update for trafficserver
• openEuler 24.03 LTS SP4 update for trafficserver
• openEuler 24.03 LTS SP3 update for trafficserver