CVE-2025-31699
Apache Traffic Server: Origin connection still owed a request body is reused, enabling request smuggling
- State
- Published
- Severity
- 9.1 Critical
- Published
- Oct 21, 2026
- Updated
- Oct 23, 2026
- Reserved
- Apr 1, 2025
Description
Apache Traffic Server can return an origin connection to the shared pool while the origin is still waiting on a request body the client declared but never fully sent, including when the client used Expect: 100-continue. The origin then reads a later request on that connection as leftover body data, which lets an attacker smuggle requests past ATS access controls, disrupt other users' requests, or poison the cache.
This issue affects Apache Traffic Server: from 8.0.0 through 8.1.11, from 9.0.0 through 9.2.15, from 10.0.0 through 10.1.4, 10.2.0.
Users are recommended to upgrade to version 9.2.16, 10.1.5, or 10.2.1, which fix the issue.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 9.1 Critical | CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:H/VA:L/SC:H/SI:H/SA:L | apache |
| 3.1 | 8.9 High | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:L | apache |
Weaknesses
- CWE-444 Inconsistent Interpretation of HTTP Requests
Affected Products
| Product | Versions |
|---|---|
Apache Traffic ServerApache Software Foundation |
|
References
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