← Vulnerability feed

Vulnerability record · CVE-2026-53540 · published 22 June 2026

CVE-2026-53540: Fastapiexpert python-multipart vulnerability

Fastapiexpert · Python Multipart

Python-Multipart is a streaming multipart parser for Python. Prior to 0.0.31, parse_form() did not validate the Content-Length header before using it to bound its chunked read of the request body. A negative Content-Length turned the bounded read into a read-until-EOF, so the entire body was loaded into memory in a single read instead of in fixed-size chunks. This vulnerability is fixed in 0.0.31.

3.7 CVSS 3.1 Low EPSS 0.34% · top 74.9% CWE-1284 · CWE-1284
3.7CVSS 3.1 base score
0.34%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
1References
26 Jun 2026Last modified by NVD

Description

Python-Multipart is a streaming multipart parser for Python. Prior to 0.0.31, parse_form() did not validate the Content-Length header before using it to bound its chunked read of the request body. A negative Content-Length turned the bounded read into a read-until-EOF, so the entire body was loaded into memory in a single read instead of in fixed-size chunks. This vulnerability is fixed in 0.0.31.

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://github.com/Kludex/python-multipart/security/advisories/GHSA-v9pg-7xvm-68hf Vendor Advisory

Track CVE-2026-53540 inside VULONE

Watch it alongside the ransomware crews, C2 infrastructure and forum chatter that reference it, query it through the API and pull it into your SIEM over TAXII.

Start free Open in platform

Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

7.5CVE-2026-53539Fastapiexpert python-multipart uncontrolled resource consumption vulnerabilityPython-Multipart is a streaming multipart parser for Python. Prior to 0.0.30, when parsing application/x-www-form-urlencoded bodies, QuerystringParse…EPSS 0.46%7.5CVE-2026-24486Fastapiexpert python-multipart path traversal vulnerabilityPython-Multipart is a streaming multipart parser for Python. Prior to version 0.0.22, a Path Traversal vulnerability exists when using non-default co…EPSS 2.2%7.5CVE-2024-24762Fastapiexpert python-multipart uncontrolled resource consumption vulnerability`python-multipart` is a streaming multipart parser for Python. When using form data, `python-multipart` uses a Regular Expression to parse the HTTP `…EPSS 1.5%5.3CVE-2026-53537Fastapiexpert python-multipart improper input validation vulnerabilityPython-Multipart is a streaming multipart parser for Python. Prior to 0.0.30, parse_options_header parsed Content-Disposition (and Content-Type) head…EPSS 0.29%5.3CVE-2026-40347Fastapiexpert python-multipart uncontrolled resource consumption vulnerabilityPython-Multipart is a streaming multipart parser for Python. Versions prior to 0.0.26 have a denial of service vulnerability when parsing crafted `mu…EPSS 0.42%3.7CVE-2026-53538Fastapiexpert python-multipart interpretation conflict vulnerabilityPython-Multipart is a streaming multipart parser for Python. Prior to 0.0.30, QuerystringParser treated ; as a field separator in application/x-www-f…EPSS 0.26%7.8CVE-2010-3904Linux Kernel RDS rds_page_copy_user Improper Input Validation Privilege EscalationThe rds_page_copy_user function in net/rds/page.c in the Linux kernel before 2.6.36 fails to properly validate addresses obtained from user space. A …KEVEPSS 14%analysed9.8CVE-2022-20699Cisco Small Business RV Series Routers Stack Buffer OverflowCisco Small Business RV160, RV260, RV340 and RV345 series routers contain a stack-based buffer overflow (CWE-121) that can be triggered remotely with…KEVEPSS 72%analysed

Source: NIST National Vulnerability Database (record CVE-2026-53540), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.