Upstream information

CVE-2026-53538 at MITRE

Description

Python-Multipart is a streaming multipart parser for Python. Prior to 0.0.30, QuerystringParser treated ; as a field separator in application/x-www-form-urlencoded bodies, in addition to &. The WHATWG URL standard, modern browsers, and Python's urllib.parse (since the CVE-2021-23336 fix) treat only & as a separator. This creates a parser differential: the same bytes are tokenized into different fields than a WHATWG compliant intermediary would produce, allowing an attacker to smuggle extra form fields past an upstream body inspecting component. This vulnerability is fixed in 0.0.30.

SUSE information

Overall state of this security issue: Pending

This issue is currently rated as having low severity.

CVSS v3 Scores
CVSS detail CNA (GitHub) SUSE
Base Score 3.7 3.7
Vector CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
Attack Vector Network Network
Attack Complexity High High
Privileges Required None None
User Interaction None None
Scope Unchanged Unchanged
Confidentiality Impact None None
Integrity Impact Low Low
Availability Impact None None
CVSSv3 Version 3.1 3.1
CVSS v4 Scores
CVSS detail SUSE
Base Score 6.3
Vector CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
Attack Vector Network
Attack Complexity High
Attack Requirements None
Privileges Required None
User Interaction None
Vulnerable System Confidentiality Impact None
Vulnerable System Integrity Impact Low
Vulnerable System Availability Impact None
Subsequent System Confidentiality Impact None
Subsequent System Integrity Impact None
Subsequent System Availability Impact None
CVSSv4 Version 4.0
SUSE Bugzilla entry: 1268496 [IN_PROGRESS]

SUSE Security Advisories:

List of released packages

Product(s) Fixed package version(s) References
SUSE Linux Enterprise Server 16.0
SUSE Linux Enterprise Server for SAP applications 16.0
  • python313-python-multipart >= 0.0.20-160000.5.1
Patchnames:
SUSE-SLES-16.0-1088
openSUSE Leap 16.0
  • python313-python-multipart >= 0.0.20-160000.5.1
Patchnames:
openSUSE-Leap-16.0-1088
openSUSE Tumbleweed
  • python311-python-multipart >= 0.0.32-1.1
  • python313-python-multipart >= 0.0.32-1.1
  • python314-python-multipart >= 0.0.32-1.1
Patchnames:
openSUSE-Tumbleweed-2026-11099


Status of this issue by product and package

Please note that this evaluation state might be work in progress, incomplete or outdated. Also information for service packs in the LTSS phase is only included for issues meeting the LTSS criteria. If in doubt, feel free to contact us for clarification. The updates are grouped by state of their lifecycle. SUSE product lifecycles are documented on the lifecycle page.

Product(s) Source package State
Products under general support and receiving all security fixes.
SUSE Linux Enterprise Server 16.0 python-python-multipart Released
SUSE Linux Enterprise Server 16.1 python-python-multipart Affected
SUSE Linux Enterprise Server for SAP applications 16.0 python-python-multipart Released
SUSE Linux Enterprise Server for SAP applications 16.1 python-python-multipart Affected
openSUSE Leap 16.0 python-python-multipart Affected
Products past their end of life and not receiving proactive updates anymore.
openSUSE Leap 15.6 python-python-multipart Released


SUSE Timeline for this CVE

CVE page created: Tue Jun 16 00:35:50 2026
CVE page last modified: Mon Jul 6 18:59:47 2026