CVE-2026-33930
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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.38%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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 8.1.9, 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.
- CVSS 4.0
- 8.2 HIGHCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 0.38% probability · 32th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-121
- Affected
- apache/traffic server
- Source
- security@apache.org
References
- https://lists.apache.org/thread/5prl9glcm9g2swnq9hqxvnokylm1gr6dVendor Advisory, Mailing List
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.