CVE-2026-54277

Severity CVSS v4.0:

MEDIUM

Type:

Unavailable / Other

Publication date:

22/06/2026

Last modified:

30/06/2026

Description

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.

Impact

Vector 4.0

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U CVSS v4.0 Severity and Metrics:

Base Score: 6.60 MEDIUM
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U

Attack Vector (AV): Network
Attack Complexity (AC): Low
Attack Requirements (AT): None
Privileges Required (PR): None
User Interaction (UI): None
Confidentiality (VC): None
Integrity (VI): None
Availability (VA): High
Confidentiality (SC): None
Integrity (SI): None
Availability (SA): None
Exploit Maturity (E): Unreported

Base Score 4.0

6.60

Severity 4.0

MEDIUM

Vector 3.x

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H CVSS v3.1 Severity and Metrics:

Base Score: 7.50 HIGH
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope (S): Unchanged
Confidentiality (C): None
Integrity (I): None
Availability (A): High