CVE-2026-54278: CWE-409: Improper Handling of Highly Compressed Data (Data Amplification) in aio-libs aiohttp
AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to 3.14.1, during cleanup it is possible for a compressed request body to be decompressed into memory in one chunk. An attacker may be able to send a compressed payload in specific situations that could be decompressed into memory, potentially leading to DoS (a zip bomb edge case). This vulnerability is fixed in 3.14.1.
AI Analysis
Technical Summary
The vulnerability in aiohttp versions before 3.14.1 involves improper handling of highly compressed data during cleanup. Specifically, a compressed request body can be decompressed entirely into memory at once, which may allow an attacker to cause a denial-of-service by sending a compressed payload that expands significantly (zip bomb). This is classified under CWE-409 (Improper Handling of Highly Compressed Data). The vulnerability has a CVSS 4.0 score of 6.6 (medium severity). The fix is included in aiohttp 3.14.1.
Potential Impact
An attacker can exploit this vulnerability by sending a specially crafted compressed HTTP request body that decompresses into a large amount of memory during cleanup, potentially exhausting server resources and causing a denial-of-service condition. There is no indication of privilege escalation, data disclosure, or other impacts beyond resource exhaustion.
Mitigation Recommendations
Upgrade aiohttp to version 3.14.1 or later, where this vulnerability is fixed. No other official remediation or temporary fixes are indicated. Patch status is confirmed by the vendor advisory stating the fix is in 3.14.1.
CVE-2026-54278: CWE-409: Improper Handling of Highly Compressed Data (Data Amplification) in aio-libs aiohttp
Description
AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to 3.14.1, during cleanup it is possible for a compressed request body to be decompressed into memory in one chunk. An attacker may be able to send a compressed payload in specific situations that could be decompressed into memory, potentially leading to DoS (a zip bomb edge case). 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 improper handling of highly compressed data during cleanup. Specifically, a compressed request body can be decompressed entirely into memory at once, which may allow an attacker to cause a denial-of-service by sending a compressed payload that expands significantly (zip bomb). This is classified under CWE-409 (Improper Handling of Highly Compressed Data). The vulnerability has a CVSS 4.0 score of 6.6 (medium severity). The fix is included in aiohttp 3.14.1.
Potential Impact
An attacker can exploit this vulnerability by sending a specially crafted compressed HTTP request body that decompresses into a large amount of memory during cleanup, potentially exhausting server resources and causing a denial-of-service condition. There is no indication of privilege escalation, data disclosure, or other impacts beyond resource exhaustion.
Mitigation Recommendations
Upgrade aiohttp to version 3.14.1 or later, where this vulnerability is fixed. No other official remediation or temporary fixes are indicated. 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: 6a39735ceed863c81e39628f
Added to database: 06/22/2026, 17:39:40 UTC
Last enriched: 06/29/2026, 21:51:45 UTC
Last updated: 08/05/2026, 16:51:06 UTC
Views: 140
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