AIOHTTP: CRLF injection in multipart headers
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- —
- Confidentiality · integrity · availability
- None · Low · None
- Fix status
- Partial Red Hat: 10 without a fix
Attack profile from CVSS 4.0 · CNA. Fix status from CNA, GitHub and Red Hat.
Summary
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.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| aio-libs | aiohttp | before 3.14.0 | 3.14.0 | Patch available | CNA |
| — | aiohttp (PyPI) | before 3.14.0 | 3.14.0 | Patch available | GHSA-m6qw-4cw2-hm4m |
- aiohttp Vendoraio-libs Affected before 3.14.0 Fixed in 3.14.0 Patch available CNA
- aiohttp (PyPI) Vendor— Affected before 3.14.0 Fixed in 3.14.0 Patch available GHSA-m6qw-4cw2-hm4m
Remediation
- Fix · CNA aiohttp (aio-libs) Fixed in 3.14.0
- Fix · GHSA-m6qw-4cw2-hm4m aiohttp (PyPI) Fixed in 3.14.0 Advisory →
Vendor assessments
Red Hat
Red Hat rating: Low. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Exploit Intelligence | Affected | No fix yet: Fix deferred |
| Migration Toolkit for Applications 8 | Affected | No fix yet: Fix deferred |
| OpenShift Lightspeed | Affected | No fix yet: Fix deferred |
| Red Hat AI Inference Server | Affected | No fix yet: Fix deferred |
| Red Hat Ansible Automation Platform 2 | Affected | No fix yet: Fix deferred |
| Red Hat Ansible Automation Platform Ansible Core 2 | Affected | No fix yet: Fix deferred |
| Red Hat Discovery 2 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux AI (RHEL AI) 3 | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift AI (RHOAI) | Affected | No fix yet: Fix deferred |
| Red Hat Satellite 6 | Affected | No fix yet: Fix deferred |
Not affected: 1 product
- Red Hat Hardened Images
Timeline
- 2026-10-02 Threatist record created from CVE-2026-50269
- 2026-10-03 Alias added: GHSA-m6qw-4cw2-hm4m
References
More aio-libs vulnerabilities
- TI-2025-38826 aiomysql allows arbitrary access to client files through vulnerability of a malicious MySQL server CVSS 4.0HIGH 8.2
- TI-2024-15436 aiohttp.web.static(follow_symlinks=True) is vulnerable to directory traversal CVSS 3.1HIGH 7.5
- TI-2023-25769 Request smuggling in aiohttp CVSS 3.1HIGH 7.5
- TI-2023-18906 aiohttp vulnerable to HTTP request smuggling CVSS 3.1HIGH 7.5
- TI-2023-26746 aiohttp's ClientSession is vulnerable to CRLF injection via version CVSS 3.1HIGH 7.2
- TI-2026-66145 Multidict: Reference leak in CIMultiDict/MultiDict items-view union and subtraction CVSS 3.1MEDIUM 5.3
Sources
- CVE-2026-50269 · CVE Program
- CVE-2026-50269 · NVD
- FIRST EPSS
- GHSA-m6qw-4cw2-hm4m · GitHub Advisory Database · CC BY 4.0
- CVE-2026-50269 · Red Hat security data · CC BY 4.0
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