ReDoS in multipart 1.3.0 - `parse_options_header()`
Summary
| CVE | CVE-2026-28356 |
|---|---|
| State | PUBLISHED |
| Assigner | GitHub_M |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-03-12 17:16:50 UTC |
| Updated | 2026-07-21 12:17:51 UTC |
| Description | multipart is a fast multipart/form-data parser for python. Prior to 1.2.2, 1.3.1 and 1.4.0-dev, the parse_options_header() function in multipart.py uses a regular expression with an ambiguous alternation, which can cause exponential backtracking (ReDoS) when parsing maliciously crafted HTTP or multipart segment headers. This can be abused for denial of service (DoS) attacks against web applications using this library to parse request headers or multipart/form-data streams. The issue is fixed in 1.2.2, 1.3.1 and 1.4.0-dev. |
Risk And Classification
Primary CVSS: v3.1 7.5 HIGH from ADP
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS: 0.006990000 probability, percentile 0.490870000 (date 2026-07-21)
Problem Types: CWE-1333 | CWE-1333 CWE-1333: Inefficient Regular Expression Complexity | CWE-1333 Inefficient Regular Expression Complexity
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | ADP | CVSS | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| 3.1 | [email protected] | Secondary | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| 3.1 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | Secondary | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| 3.1 | CNA | DECLARED | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
LowPrivileges Required
NoneUser Interaction
NoneScope
UnchangedConfidentiality
NoneIntegrity
NoneAvailability
HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Defnull | Multipart | affected >= 1.3.0, < 1.3.1 | Not specified |
| CNA | Defnull | Multipart | affected < 1.2.2 | Not specified |
| ADP | Red Hat | Red Hat AI Inference Server 3.2 | unaffected 1774351144 * rpm | Not specified |
| ADP | Red Hat | Red Hat AI Inference Server 3.2 | unaffected 1774547384 * rpm | Not specified |
| ADP | Red Hat | Red Hat AI Inference Server 3.2 | unaffected 1775252598 * rpm | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI 2.25 | unaffected 1776247907 * rpm | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI 2.25 | unaffected 1776338381 * rpm | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI 2.25 | unaffected 1782397826 * rpm | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI 2.25 | unaffected 1783998774 * rpm | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI 2.25 | unaffected 1783998857 * rpm | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI 3.3 | unaffected 1782996080 * rpm | Not specified |
| ADP | Red Hat | Lightspeed Core | Not specified | Not specified |
| ADP | Red Hat | Lightspeed Core | Not specified | Not specified |
| ADP | Red Hat | OpenShift Lightspeed | Not specified | Not specified |
| ADP | Red Hat | OpenShift Lightspeed | Not specified | Not specified |
| ADP | Red Hat | Red Hat AI Inference Server | Not specified | Not specified |
| ADP | Red Hat | Red Hat AI Inference Server | Not specified | Not specified |
| ADP | Red Hat | Red Hat AI Inference Server | Not specified | Not specified |
| ADP | Red Hat | Red Hat AI Inference Server | Not specified | Not specified |
| ADP | Red Hat | Red Hat Ansible Automation Platform 2 | Not specified | Not specified |
| ADP | Red Hat | Red Hat Ansible Automation Platform 2 | Not specified | Not specified |
| ADP | Red Hat | Red Hat Ansible Automation Platform 2 | Not specified | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux AI RHEL AI 3 | Not specified | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux AI RHEL AI 3 | Not specified | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux AI RHEL AI 3 | Not specified | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux AI RHEL AI 3 | Not specified | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux AI RHEL AI 3 | Not specified | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux AI RHEL AI 3 | Not specified | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux AI RHEL AI 3 | Not specified | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI RHOAI | Not specified | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI RHOAI | Not specified | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI RHOAI | Not specified | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI RHOAI | Not specified | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI RHOAI | Not specified | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI RHOAI | Not specified | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI RHOAI | Not specified | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI RHOAI | Not specified | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI RHOAI | Not specified | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI RHOAI | Not specified | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI RHOAI | Not specified | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI RHOAI | Not specified | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI RHOAI | Not specified | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI RHOAI | Not specified | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI RHOAI | Not specified | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI RHOAI | Not specified | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI RHOAI | Not specified | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI RHOAI | Not specified | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI RHOAI | Not specified | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI RHOAI | Not specified | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI RHOAI | Not specified | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI RHOAI | Not specified | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI RHOAI | Not specified | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI RHOAI | Not specified | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI RHOAI | Not specified | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI RHOAI | Not specified | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI RHOAI | Not specified | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI RHOAI | Not specified | Not specified |
| ADP | Red Hat | Red Hat Satellite 6 | Not specified | Not specified |
| ADP | Red Hat | Red Hat Satellite 6 | Not specified | Not specified |
| ADP | Red Hat | Red Hat Satellite 6 | Not specified | Not specified |
| ADP | Red Hat | Red Hat Satellite 6 | Not specified | Not specified |
| ADP | Red Hat | Red Hat Satellite 6 | Not specified | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| access.redhat.com/errata/RHSA-2026:5809 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:6761 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:42644 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:10184 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:37275 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/security/cve/CVE-2026-28356 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| bugzilla.redhat.com/show_bug.cgi | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | bugzilla.redhat.com | |
| security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-28356.json | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | security.access.redhat.com | |
| github.com/defnull/multipart/security/advisories/GHSA-p2m9-wcp5-6qw3 | [email protected] | github.com | |
| access.redhat.com/errata/RHSA-2026:6762 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
Additional Advisory Data
| Source | Time | Event |
|---|---|---|
| ADP | 2026-03-12T18:01:57.290Z | Reported to Red Hat. |
| ADP | 2026-03-12T16:45:01.070Z | Made public. |
Solutions
ADP: RHSA-2026:6761: Red Hat AI Inference Server 3.2
ADP: RHSA-2026:5809: Red Hat AI Inference Server 3.2
ADP: RHSA-2026:6762: Red Hat AI Inference Server 3.2
ADP: RHSA-2026:10184: Red Hat OpenShift AI 2.25
ADP: RHSA-2026:42644: Red Hat OpenShift AI 2.25
ADP: RHSA-2026:37275: Red Hat OpenShift AI 3.3
Workarounds
ADP: Red Hat has investigated whether a possible mitigation exists for this issue, and has not been able to identify a practical example. Please update the affected package as soon as possible.
There are currently no legacy QID mappings associated with this CVE.