CVE-2026-42561
Medium
Elevated severity or exploit probability.
CVSS base
7.5
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS — probability of exploitation (30 days)
0.8%
56.4th percentile
CISA KEV
Not listed
Weakness / dates
CWE-606
Published 2026-05-13 · modified 2026-08-07
Description
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.
References
- https://github.com/Kludex/python-multipart/security/advisories/GHSA-pp6c-gr5w-3c5g
- https://access.redhat.com/errata/RHSA-2026:37275
- https://access.redhat.com/errata/RHSA-2026:42132
- https://access.redhat.com/errata/RHSA-2026:42142
- https://access.redhat.com/errata/RHSA-2026:43038
- https://access.redhat.com/errata/RHSA-2026:44696
- https://access.redhat.com/errata/RHSA-2026:51194
- https://access.redhat.com/errata/RHSA-2026:51219
- https://access.redhat.com/errata/RHSA-2026:51357
- https://access.redhat.com/security/cve/CVE-2026-42561
- https://bugzilla.redhat.com/show_bug.cgi?id=2477309
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-42561.json