What’s Vulnerable › Vulnerabilities
CVE-2026-33930: Apache Traffic Server: Buffer overflow via Host field that has a long string value
- Severity: medium (CVSS 5.9 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.6% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2026-07-29 · updated 2026-10-01
- Weakness: CWE-121
Description
Apache Traffic Server copies the client Host header into a fixed-size stack buffer without a bound during redirect handling, so an over-long Host header overflows the stack when redirect following is enabled. This issue affects Apache Traffic Server: from 8.0.0 through 8.1.11, from 9.0.0 through 9.2.14, from 10.0.0 through 10.1.3. Users are recommended to upgrade to version 9.2.15 or 10.1.4, which fix the issue.
Affected products
- Apache Software Foundation Apache Traffic Server: from 8.0.0 through 8.1.9; from 9.0.0 before 9.2.15; from 10.0.0 before 10.1.4 — fixed in 10.1.4, 9.2.15
How to fix
Upgrade to a fixed version: Apache Software Foundation Apache Traffic Server 10.1.4, 9.2.15. Check the vendor advisory for mitigations.
References
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