CVE-2026-54277: CWE-770: Allocation of Resources Without Limits or Throttling in aio-libs aiohttp
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.
AI Analysis
Technical Summary
The vulnerability in aiohttp versions before 3.14.1 involves the ability to bypass the max_line_size check in the HTTP request parser when using the optimized C parser. This allows an attacker to send HTTP request lines larger than intended, causing the parser to allocate excessive memory without limits or throttling. This uncontrolled resource allocation can lead to denial of service conditions. The flaw is categorized under CWE-770 (Allocation of Resources Without Limits or Throttling). The issue is resolved in version 3.14.1 of aiohttp.
Potential Impact
An attacker can exploit this vulnerability by sending specially crafted HTTP requests with oversized lines to a server using the vulnerable aiohttp versions with the default C parser. This can cause the server to consume excessive memory, potentially resulting in denial of service due to resource exhaustion. There is no indication of privilege escalation or data compromise from the provided data.
Mitigation Recommendations
Upgrade aiohttp to version 3.14.1 or later, where this vulnerability is fixed. No other mitigation or temporary workaround is indicated in the available data. Patch status is confirmed by the vendor advisory stating the fix is in 3.14.1.
CVE-2026-54277: CWE-770: Allocation of Resources Without Limits or Throttling in aio-libs aiohttp
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.
CVSS v4.0
Score 6.6medium
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability in aiohttp versions before 3.14.1 involves the ability to bypass the max_line_size check in the HTTP request parser when using the optimized C parser. This allows an attacker to send HTTP request lines larger than intended, causing the parser to allocate excessive memory without limits or throttling. This uncontrolled resource allocation can lead to denial of service conditions. The flaw is categorized under CWE-770 (Allocation of Resources Without Limits or Throttling). The issue is resolved in version 3.14.1 of aiohttp.
Potential Impact
An attacker can exploit this vulnerability by sending specially crafted HTTP requests with oversized lines to a server using the vulnerable aiohttp versions with the default C parser. This can cause the server to consume excessive memory, potentially resulting in denial of service due to resource exhaustion. There is no indication of privilege escalation or data compromise from the provided data.
Mitigation Recommendations
Upgrade aiohttp to version 3.14.1 or later, where this vulnerability is fixed. No other mitigation or temporary workaround is indicated in the available data. Patch status is confirmed by the vendor advisory stating the fix is in 3.14.1.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-06-12T17:13:32.280Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a39735beed863c81e396261
Added to database: 06/22/2026, 17:39:39 UTC
Last enriched: 06/29/2026, 21:51:40 UTC
Last updated: 08/04/2026, 13:36:27 UTC
Views: 59
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