aiohttp: CRLF injection in multipart headers
### Summary Attacker-controlled input included into multipart/payload headers can be used to modify a request to inject additional headers or similar. ### Impact 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. ### Workaround Sanitise such user input. ----- Patch: https://github.com/aio-libs/aiohttp/commit/bf88077ebb14f4c29924b8e8904cba20c55c28b8
describes (1)
Related CVEs.
| ID | severity | exploitable | ||
|---|---|---|---|---|
| CVE-2026-50269US | high7.5 | — | ||
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 mo… | ||||
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