GHSA-gm8q-m8mv-jj5m
CRITICALUnstructured has Path Traversal via Malicious MSG Attachment that Allows Arbitrary File Write
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.
Blast Radius
unstructuredReal-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
A Path Traversal vulnerability in the partition_msg function allows an attacker to write or overwrite arbitrary files on the filesystem when processing malicious MSG files with attachments.
Impact
An attacker can craft a malicious .msg file with attachment filenames containing path traversal sequences (e.g.,
../../../etc/cron.d/malicious). When processed with process_attachments=True, the library writes the attachment to an
attacker-controlled path, potentially leading to:
- Arbitrary file overwrite
- Remote code execution (via overwriting configuration files, cron jobs, or Python packages)
- Data corruption
- Denial of service
Affected Functionality
The vulnerability affects the MSG file partitioning functionality when process_attachments=True is enabled.
Vulnerability Details
The library does not sanitize attachment filenames in MSG files before using them in file write operations, allowing directory traversal sequences to escape the intended output directory.
Workarounds
Until patched, users can:
- Set
process_attachments=Falsewhen processing untrusted MSG files - Avoid processing MSG files from untrusted sources
- Implement additional filename validation before processing
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | unstructured | all versions | 0.18.18 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for unstructured. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update unstructured to 0.18.18 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-gm8q-m8mv-jj5m 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 pinpoints whether GHSA-gm8q-m8mv-jj5m is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-gm8q-m8mv-jj5m. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-gm8q-m8mv-jj5m in your dependencies?
O3 detects GHSA-gm8q-m8mv-jj5m across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.