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TI-2023-18906 Aliases CVE-2023-37276GHSA-45c4-8wx5-qw6w

aiohttp vulnerable to HTTP request smuggling

Priority HIGH 72CWE-444Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · High · None
Fix status
Partial Red Hat: 2 fixed, 4 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA, GitHub and Red Hat.

Summary

aiohttp is an asynchronous HTTP client/server framework for asyncio and Python. aiohttp v3.8.4 and earlier are bundled with llhttp v6.0.6. Vulnerable code is used by aiohttp for its HTTP request parser when available which is the default case when installing from a wheel. This vulnerability only affects users of aiohttp as an HTTP server (ie `aiohttp.Application`), you are not affected by this vulnerability if you are using aiohttp as an HTTP client library (ie `aiohttp.ClientSession`). Sending a crafted HTTP request will cause the server to misinterpret one of the HTTP header values leading to HTTP request smuggling. This issue has been addressed in version 3.8.5. Users are advised to upgrade. Users unable to upgrade can reinstall aiohttp using `AIOHTTP_NO_EXTENSIONS=1` as an environment variable to disable the llhttp HTTP request parser implementation. The pure Python implementation isn't vulnerable.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.01337 71st percentileScored 2026-11-07
Public exploit Yes 2 exploit referencesTagged by NVD
Fix Partial aiohttp (aio-libs): 3.8.5aiohttp (PyPI): 3.8.5Red Hat: 2 advisoriesRed Hat: 2 fixed, 4 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
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

VendorProductAffected versionsFixed inStatusSource
aio-libsaiohttpbefore 3.8.53.8.5Patch availableCNA
—aiohttp (PyPI)before 3.8.53.8.5Patch availableGHSA-45c4-8wx5-qw6w
  • aiohttp Vendoraio-libs Affected before 3.8.5 Fixed in 3.8.5 Patch available CNA
  • aiohttp (PyPI) Vendor— Affected before 3.8.5 Fixed in 3.8.5 Patch available GHSA-45c4-8wx5-qw6w

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:aiohttp:aiohttp:*:*:*:*:*:*:*:*up to 3.8.4VulnerableAiohttp
  • cpe:2.3:a:aiohttp:aiohttp:*:*:*:*:*:*:*:* Versions up to 3.8.4 Vulnerable ·Aiohttp

Remediation

  • Fix · CNA aiohttp (aio-libs) Fixed in 3.8.5
  • Fix · GHSA-45c4-8wx5-qw6w aiohttp (PyPI) Fixed in 3.8.5 Advisory →

Red Hat 2 advisories

  • RHSA-2024:2010 Released 2024-04-23 · Red Hat rating Important
    Satellite 6.15.0 release
    • Red Hat Satellite 6.15 for RHEL 8 foreman-3.9.1.6-1.el8sat, foreman-cli-3.9.1.6-1.el8sat, foreman-debug-3.9.1.6-1.el8sat +28
  • RHSA-2024:1878 Released 2024-04-18 · Red Hat rating Moderate
    RHUI 4.8 Release - Security Updates, Bug Fixes, and Enhancements
    • RHUI 4 for RHEL 8 python-aiohttp-3.9.2-1.el8ui, python-cryptography-41.0.6-1.el8ui, python-django-4.2.11-1.el8ui +7

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Ansible Automation Platform 1.2AffectedNo fix planned: Will not fix
Red Hat Ansible Automation Platform 2AffectedNo fix yet
Red Hat OpenShift Data Science (RHODS)AffectedNo fix yet
Red Hat OpenStack Platform 17.1AffectedNo fix planned: Will not fix
RHUI 4 for RHEL 8Fixed RHSA-2024:1878
Red Hat Satellite 6.15 for RHEL 8Fixed RHSA-2024:2010
Not affected: 2 products
  • RHUI 4 for RHEL 8
  • Red Hat Satellite 6.15 for RHEL 8

Timeline

  1. 2026-10-02 Threatist record created from CVE-2023-37276
  2. 2026-10-03 Alias added: GHSA-45c4-8wx5-qw6w

References

Exploit 2

Patch 1

Advisory 1

Other 4

  • 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-2023-26746 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
  • TI-2023-26747 aiohttp's ClientSession is vulnerable to CRLF injection via method CVSS 3.1MEDIUM 5.3
See all 59 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences