CVE-2026-54278: CWE-409: Improper Handling of Highly Compressed Data (Data Amplification) in aio-libs aiohttp
CVE-2026-54278 is a medium severity vulnerability in aiohttp, an asynchronous HTTP client/server framework for Python. Versions prior to 3.14.1 may decompress a compressed request body into memory in one chunk during cleanup, which can lead to excessive memory consumption. This behavior can be exploited by sending a specially crafted compressed payload, potentially causing a denial of service (DoS) via a zip bomb-like data amplification. The issue is fixed in version 3.14.1.
AI Analysis
Technical Summary
The vulnerability in aiohttp before version 3.14.1 involves improper handling of highly compressed data during cleanup. Specifically, a compressed request body can be decompressed into memory as a single chunk, which may allow an attacker to cause a denial of service by sending a compressed payload that expands significantly in memory (a zip bomb edge case). This is classified under CWE-409 (Improper Handling of Highly Compressed Data). The fix was introduced in version 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. There is no indication of privilege escalation, code execution, or data disclosure. The impact is limited to resource exhaustion resulting in service disruption.
Mitigation Recommendations
Upgrade aiohttp to version 3.14.1 or later, where this vulnerability has been 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
CVE-2026-54278 is a medium severity vulnerability in aiohttp, an asynchronous HTTP client/server framework for Python. Versions prior to 3.14.1 may decompress a compressed request body into memory in one chunk during cleanup, which can lead to excessive memory consumption. This behavior can be exploited by sending a specially crafted compressed payload, potentially causing a denial of service (DoS) via a zip bomb-like data amplification. The issue is fixed in version 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 before version 3.14.1 involves improper handling of highly compressed data during cleanup. Specifically, a compressed request body can be decompressed into memory as a single chunk, which may allow an attacker to cause a denial of service by sending a compressed payload that expands significantly in memory (a zip bomb edge case). This is classified under CWE-409 (Improper Handling of Highly Compressed Data). The fix was introduced in version 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. There is no indication of privilege escalation, code execution, or data disclosure. The impact is limited to resource exhaustion resulting in service disruption.
Mitigation Recommendations
Upgrade aiohttp to version 3.14.1 or later, where this vulnerability has been 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: 06/22/2026, 17:55:30 UTC
Last updated: 06/22/2026, 20:21:52 UTC
Views: 3
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