HTTP Response Splitting Affecting aiohttp package, versions [,3.13.4)
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- published2 Apr 2026
- disclosed1 Apr 2026
- creditMingi Jung
Introduced: 1 Apr 2026
NewCVE-2026-34514 (opens in a new tab)Common Vulnerabilities and Exposures (CVE) are common identifiers for publicly known security vulnerabilities
Common Weakness Enumeration (CWE) is a category system for software weaknesses
How to fix?
Upgrade aiohttp to version 3.13.4 or higher.
Overview
Affected versions of this package are vulnerable to HTTP Response Splitting in the construction of multipart request headers when untrusted input is used for the content_type parameter. An attacker can inject arbitrary headers or manipulate HTTP requests by supplying specially crafted values.