CVE-2026-50269

AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to 3.14.0, attacker-controlled input included into multipart/payload headers can be used to modify a request to inject additional headers or similar. In the unlikely situation that an application is passing user-controlled strings into MultipartWriter.append(headers=...) or Payload.headers, then an attacker may be able to modify the request to inject headers or change the contents of the request. This vulnerability is fixed in 3.14.0.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/aio-libs/aiohttp/commit/bf88077ebb14f4c29924b8e8904cba20c55c28b8	Patch
https://github.com/aio-libs/aiohttp/security/advisories/GHSA-m6qw-4cw2-hm4m	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:aiohttp:aiohttp:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-06-22 18:16

Updated : 2026-06-26 19:39

NVD link : CVE-2026-50269

Mitre link : CVE-2026-50269

CVE.ORG link : CVE-2026-50269

JSON object : View

Products Affected

aiohttp

aiohttp

CWE

CWE-93

Improper Neutralization of CRLF Sequences ('CRLF Injection')

CWE-113

Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Request/Response Splitting')

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