Cyber Resilience

CVE-2023-47641

Aiohttp ≤ 3.8.0

Public PoC
Published
14 November 2023
Modified
03 November 2025
Patch / advisory
CVSS Score v3.1 3.4
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:N/A:N
EPSS Score 0.0083 54th percentile
Risk Priority 32 floored blend · peak EPSS

Summary

CVE-2023-47641 is a low-severity HTTP Request/Response Smuggling (CWE-444) vulnerability in Aiohttp Aiohttp. Its CVSS base score is 3.4 (Low).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 46% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

aiohttp is an asynchronous HTTP client/server framework for asyncio and Python. Affected versions of aiohttp have a security vulnerability regarding the inconsistent interpretation of the http protocol. HTTP/1.1 is a persistent protocol, if both Content-Length(CL) and Transfer-Encoding(TE) header values are…

more

present it can lead to incorrect interpretation of two entities that parse the HTTP and we can poison other sockets with this incorrect interpretation. A possible Proof-of-Concept (POC) would be a configuration with a reverse proxy(frontend) that accepts both CL and TE headers and aiohttp as backend. As aiohttp parses anything with chunked, we can pass a chunked123 as TE, the frontend entity will ignore this header and will parse Content-Length. The impact of this vulnerability is that it is possible to bypass any proxy rule, poisoning sockets to other users like passing Authentication Headers, also if it is present an Open Redirect an attacker could combine it to redirect random users to another website and log the request. This vulnerability has been addressed in release 3.8.0 of aiohttp. Users are advised to upgrade. There are no known workarounds for this vulnerability.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-37276Same product: Aiohttp Aiohttp
CVE-2025-69225Same product: Aiohttp Aiohttp
CVE-2024-52304Same product: Aiohttp Aiohttp
CVE-2023-47627Same product: Aiohttp Aiohttp
CVE-2025-53643Same product: Aiohttp Aiohttp
CVE-2025-69224Same product: Aiohttp Aiohttp
CVE-2026-34515Same product: Aiohttp Aiohttp
CVE-2026-34525Same product: Aiohttp Aiohttp
CVE-2026-50269Same product: Aiohttp Aiohttp
CVE-2026-34993Same product: Aiohttp Aiohttp

Affected Assets

aiohttp
aiohttp
≤ 3.8.0

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)
  • V4.1.3
  • V4.2.4
  • V1.5.3
  • V4.1.1

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-01 mostly match
prevents

Configuration management can enforce uniform HTTP parsing rules across intermediaries, directly mitigating inconsistent interpretation.

DE.CM-01 partial match
prevents

Network monitoring can detect smuggling attempts via anomalous HTTP traffic or logs, while eliminating the inconsistency directly aids detection of such events.

PR.IR-01 partial match
prevents

Network protections can enforce consistent HTTP proxy/firewall behavior to block smuggling, and removing the weakness helps prevent unauthorized access via request smuggling.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Security testing can detect HTTP request smuggling vulnerabilities in intermediary components.

degrades

Network security controls can enforce consistent HTTP parsing and proxy behavior that mitigates request smuggling.

degrades

Secure network services include hardening proxies and gateways against inconsistent HTTP interpretation.

prevents

Secure SDLC practices require threat modeling and testing for HTTP parsing inconsistencies in intermediaries.

prevents

Application security requirements can mandate strict HTTP message validation and canonicalization.

prevents

Secure architecture principles include consistent protocol handling and defense-in-depth for proxies.

References