CVE-2026-33267

Apache Traffic Server: Untrusted @ headers can spoof ATS internal metadata

Improper Input Validation vulnerability in Apache Traffic Server. This issue affects Apache Traffic Server: from 9.2.0 through 9.2.14, from 10.1.0 through 10.1.3. Users are recommended to upgrade to version 9.2.15 or 10.1.4, which fixes the issue.

Affected

Apache Software Foundation · Apache Traffic Server

CVSS v4.0 APACHE

7.7 HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:H/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

CVSS v3.1 NVD

9.1 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

CVSS v3.1 APACHE

10.0 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N

EPSS

0.60% chance of exploitation in the next 30 days, 48th percentile

Published

2026-07-29

Updated

2026-07-30

Proof-of-concept exploits (1)

• Boreas37/CVE-2026-33267-PoC4★ · 2026-08-12

Security advisories

• https://lists.apache.org/thread/5prl9glcm9g2swnq9hqxvnokylm1gr6d

References

• CVE Record
• NVD entry

Related

• CVE-2025-62593
• CVE-2026-17544
• CVE-2026-32475
• CVE-2026-34908
• CVE-2026-34909
• CVE-2026-34910