Is CVE-2026-40347 actively exploited?

No active exploitation of CVE-2026-40347 has been confirmed so far. Continue monitoring, as exploit status can change.

Can CVE-2026-40347 be exploited remotely?

Yes. CVE-2026-40347 is exploitable remotely over the network (CVSS attack vector: Network).

What is the CVSS score of CVE-2026-40347?

CVE-2026-40347 has a CVSS score of 5.3 (MEDIUM).

HOME VULNERABILITIESCVE-2026-40347

MEDIUM

CVE-2026-40347

CWE-400Published: April 18, 2026· Updated: Apr 24, 2026

5.3

CVSS v3.1

EPSS:0.01%probability of exploitation in 30 daysPercentile:2.8th

Official Description

Python-Multipart is a streaming multipart parser for Python. Versions prior to 0.0.26 have a denial of service vulnerability when parsing crafted `multipart/form-data` requests with large preamble or epilogue sections. Upgrade to version 0.0.26 or later, which skips ahead to the next boundary candidate when processing leading CR/LF data and immediately discards epilogue data after the closing boundary.

NVD Source

Technical Analysis

CVE-2026-40347 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.