CVE-2026-425617.5HighCWE-770

CVE-2026-42561: Python-Multipart: Denial of Service via unbounded multipart part headers

Kludex · python-multipart

Vendor fix available · Affected: Kludex python-multipart · Exploitation: unlikely (under 1%)

Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.

0.7%probability of exploitation in the next 30 days

55th percentile

050100

Higher than 55% of scored CVEs

7.5HighCVSS 3.1

LowMediumHighCrit.

DescriptionCVE.org

Python-Multipart is a streaming multipart parser for Python. Prior to 0.0.27, python-multipart has a denial of service vulnerability in multipart part header parsing. When parsing multipart/form-data, MultipartParser previously had no limit on the number of part headers or the size of an individual part header. An attacker could send a request with either many repeated headers without terminating the header block or a single very large header value, causing excessive CPU work before request rejection or completion. This vulnerability is fixed in 0.0.27.

Affected products1

From the CVE record. A product or version that is not listed is unknown, not unaffected.

Kludex · python-multipart< 0.0.27

On the Atlas

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Exploitation: Unlikely (under 1%). EPSS under 1%, or no score yet.
CISA KEV: Not listed
Public check: No public nuclei template
Weakness: Allocation Without Limits · Denial of Service
Vendor: Kludex
Published: May 2026
Band: Unlikely (under 1%), May 2026

CoverageNo articles yet

No CyberSIXT article names CVE-2026-42561 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.