CVE-2026-34519
AIOHTTP: HTTP response splitting via \r in reason phrase
- State
- Published
- Severity
- 2.7 Low
- Published
- Apr 1, 2026
- Updated
- Apr 2, 2026
- Reserved
- Mar 30, 2026
Description
AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to version 3.13.4, an attacker who controls the reason parameter when creating a Response may be able to inject extra headers or similar exploits. This issue has been patched in version 3.13.4.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 2.7 Low | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U | GitHub_M |
Weaknesses
- CWE-113 Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Request/Response Splitting')
Affected Products
| Product | Versions |
|---|---|
aiohttpaio-libs |
|
References
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