CVE-2026-40347: CWE-400: Uncontrolled Resource Consumption in Kludex python-multipart
A denial of service vulnerability exists in python-multipart versions prior to 0. 0. 26 due to uncontrolled resource consumption when parsing crafted multipart/form-data requests with large preamble or epilogue sections. The issue is resolved in version 0. 0. 26 and later by improving boundary processing and discarding epilogue data promptly.
AI Analysis
Technical Summary
The python-multipart library before version 0.0.26 suffers from a denial of service vulnerability (CWE-400, CWE-834) caused by uncontrolled resource consumption when handling multipart/form-data requests containing large preamble or epilogue sections. This can cause the parser to consume excessive resources, leading to service disruption. The vulnerability is addressed in version 0.0.26 by skipping ahead to the next boundary candidate when processing leading CR/LF data and discarding epilogue data immediately after the closing boundary.
Potential Impact
Successful exploitation results in denial of service due to resource exhaustion during parsing of specially crafted multipart/form-data requests. There is no impact on confidentiality or integrity. The CVSS 3.1 base score is 5.3 (medium severity), reflecting network attack vector, no privileges required, no user interaction, and impact limited to availability.
Mitigation Recommendations
Upgrade python-multipart to version 0.0.26 or later to apply the fix that mitigates this vulnerability. Patch status is not explicitly confirmed in vendor advisories, but the description clearly states that upgrading to 0.0.26 or later resolves the issue. No other mitigations are indicated.
CVE-2026-40347: CWE-400: Uncontrolled Resource Consumption in Kludex python-multipart
Description
A denial of service vulnerability exists in python-multipart versions prior to 0. 0. 26 due to uncontrolled resource consumption when parsing crafted multipart/form-data requests with large preamble or epilogue sections. The issue is resolved in version 0. 0. 26 and later by improving boundary processing and discarding epilogue data promptly.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The python-multipart library before version 0.0.26 suffers from a denial of service vulnerability (CWE-400, CWE-834) caused by uncontrolled resource consumption when handling multipart/form-data requests containing large preamble or epilogue sections. This can cause the parser to consume excessive resources, leading to service disruption. The vulnerability is addressed in version 0.0.26 by skipping ahead to the next boundary candidate when processing leading CR/LF data and discarding epilogue data immediately after the closing boundary.
Potential Impact
Successful exploitation results in denial of service due to resource exhaustion during parsing of specially crafted multipart/form-data requests. There is no impact on confidentiality or integrity. The CVSS 3.1 base score is 5.3 (medium severity), reflecting network attack vector, no privileges required, no user interaction, and impact limited to availability.
Mitigation Recommendations
Upgrade python-multipart to version 0.0.26 or later to apply the fix that mitigates this vulnerability. Patch status is not explicitly confirmed in vendor advisories, but the description clearly states that upgrading to 0.0.26 or later resolves the issue. No other mitigations are indicated.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-04-10T22:50:01.358Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69e389f6bdfbbecc597650d2
Added to database: 4/18/2026, 1:41:10 PM
Last enriched: 4/18/2026, 1:53:35 PM
Last updated: 4/19/2026, 5:34:54 AM
Views: 10
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