GHSA-wp53-j4wj-2cfg is a high-severity (CVSS 8.6) Path Traversal vulnerability in python-multipart. 1 public exploit reference exists, so weaponization risk is real. A fix is available for python-multipart — see the affected versions and patch details below.
Python-Multipart has Arbitrary File Write via Non-Default Configuration
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-wp53-j4wj-2cfg.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
GHSA-wp53-j4wj-2cfg plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 378,156 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
python-multipartReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
Summary
A Path Traversal vulnerability exists when using non-default configuration options UPLOAD_DIR and UPLOAD_KEEP_FILENAME=True. An attacker can write uploaded files to arbitrary locations on the filesystem by crafting a malicious filename.
Details
When UPLOAD_DIR is set and UPLOAD_KEEP_FILENAME is True, the library constructs the file path using os.path.join(file_dir, fname). Due to the behavior of os.path.join(), if the filename begins with a /, all preceding path components are discarded:
os.path.join("/upload/dir", "/etc/malicious") == "/etc/malicious"
This allows an attacker to bypass the intended upload directory and write files to arbitrary paths.
Affected Configuration
Projects are only affected if all of the following are true:
UPLOAD_DIRis setUPLOAD_KEEP_FILENAMEis set to True- The uploaded file exceeds
MAX_MEMORY_FILE_SIZE(triggering a flush to disk)
The default configuration is not vulnerable.
Impact
Arbitrary file write to attacker-controlled paths on the filesystem.
Mitigation
Upgrade to version 0.0.22, or avoid using UPLOAD_KEEP_FILENAME=True in project configurations.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | python-multipart | all versions | 0.0.22pip install --upgrade 'python-multipart==0.0.22' |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Python-Multipart 0.0.22 - Path Traversal
by jefersoncardoso.dev · Apr 30, 2026
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for python-multipart, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update python-multipart to 0.0.22 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-wp53-j4wj-2cfg is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-wp53-j4wj-2cfg can be triaged on real exposure rather than presence alone.
Tailored to GHSA-wp53-j4wj-2cfg. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat AI Inference Server 3.2 | rhaiis/vllm-cuda-rhel9:1772160593 | RHSA-2026:3461 |
| Red Hat AI Inference Server 3.2 | rhaiis/vllm-rocm-rhel9:1772160625 | RHSA-2026:3462 |
| Red Hat Ansible Automation Platform 2.6 | ansible-automation-platform-26/lightspeed-chatbot-rhel9:1772204398 | RHSA-2026:3960 |
| Red Hat OpenShift AI 2.25 | rhoai/odh-feature-server-rhel9:1776338381 | RHSA-2026:10184 |
| Red Hat OpenShift AI 2.25 | rhoai/odh-vllm-gaudi-rhel9:1772093278 | RHSA-2026:3782 |
| Red Hat OpenShift AI 2.25 | rhoai/odh-vllm-cuda-rhel9:1783998774 | RHSA-2026:42644 |
| Red Hat OpenShift AI 3.3 | rhoai/odh-vllm-cpu-rhel9:1778264363 | RHSA-2026:19712 |
| Red Hat OpenShift AI 3.3 | rhoai/odh-vllm-gaudi-rhel9:1770956034 | RHSA-2026:3713 |
Frequently Asked Questions
Is GHSA-wp53-j4wj-2cfg in your dependencies?
O3 Security finds GHSA-wp53-j4wj-2cfg across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.