CVE-2026-54277

AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to 3.14.1, it is possible to bypass the max_line_size check in parts of an HTTP request in the C parser. If using the optimised C parser (the default in pre-built wheels), then an attacker may be able to send oversized lines through the HTTP parser and use an excessive amount of memory, potentially leading to DoS. This vulnerability is fixed in 3.14.1.

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/5ab61bb4cd88f19b712f12c7c9295fe262bf804d	Patch
https://github.com/aio-libs/aiohttp/security/advisories/GHSA-63hw-fmq6-xxg2	Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

30 Jun 2026, 18:11

Type	Values Removed	Values Added
References	~~() https://github.com/aio-libs/aiohttp/commit/5ab61bb4cd88f19b712f12c7c9295fe262bf804d -~~	() https://github.com/aio-libs/aiohttp/commit/5ab61bb4cd88f19b712f12c7c9295fe262bf804d - Patch
References	~~() https://github.com/aio-libs/aiohttp/security/advisories/GHSA-63hw-fmq6-xxg2 -~~	() https://github.com/aio-libs/aiohttp/security/advisories/GHSA-63hw-fmq6-xxg2 - Vendor Advisory
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 7.5
First Time		Aiohttp Aiohttp aiohttp
CPE		cpe:2.3:a:aiohttp:aiohttp::::::::

22 Jun 2026, 18:28

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-22 18:16

Updated : 2026-06-30 18:11

NVD link : CVE-2026-54277

Mitre link : CVE-2026-54277

CVE.ORG link : CVE-2026-54277

JSON object : View

Products Affected

aiohttp

aiohttp

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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