GHSA-5h86-8mv2-jq9f is a medium-severity (CVSS 5.9) Path Traversal vulnerability in aiohttp. 14 public exploit references exist, so weaponization risk is real. A fix is available for aiohttp — see the affected versions and patch details below.
aiohttp is vulnerable to directory traversal
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
Exploitation and automatability from CISA’s SSVC triage for GHSA-5h86-8mv2-jq9f.
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-5h86-8mv2-jq9f 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 377,166 CVEs with a current EPSS score, this one falls in the 50–90% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
aiohttpReal-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
Improperly configuring static resource resolution in aiohttp when used as a web server can result in the unauthorized reading of arbitrary files on the system.
Details
When using aiohttp as a web server and configuring static routes, it is necessary to specify the root path for static files. Additionally, the option 'follow_symlinks' can be used to determine whether to follow symbolic links outside the static root directory. When 'follow_symlinks' is set to True, there is no validation to check if a given file path is within the root directory.This can lead to directory traversal vulnerabilities, resulting in unauthorized access to arbitrary files on the system, even when symlinks are not present.
i.e. An application is only vulnerable with setup code like:
app.router.add_routes([
web.static("/static", "static/", follow_symlinks=True), # Remove follow_symlinks to avoid the vulnerability
])
Impact
This is a directory traversal vulnerability with CWE ID 22. When using aiohttp as a web server and enabling static resource resolution with follow_symlinks set to True, it can lead to this vulnerability. This vulnerability has been present since the introduction of the follow_symlinks parameter.
Workaround
Even if upgrading to a patched version of aiohttp, we recommend following these steps regardless.
If using follow_symlinks=True outside of a restricted local development environment, disable the option immediately. This option is NOT needed to follow symlinks which point to a location within the static root directory, it is only intended to allow a symlink to break out of the static directory. Even with this CVE fixed, there is still a substantial risk of misconfiguration when using this option on a server that accepts requests from remote users.
Additionally, aiohttp has always recommended using a reverse proxy server (such as nginx) to handle static resources and not to use these static resources in aiohttp for production environments. Doing so also protects against this vulnerability, and is why we expect the number of affected users to be very low.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | aiohttp | ≥ 1.0.5&&< 3.9.2 | 3.9.2pip install --upgrade 'aiohttp==3.9.2' |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
aiohttp 3.9.1 - directory traversal PoC
by Beatriz Fresno Naumova · Feb 4, 2026
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for aiohttp, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update aiohttp to 3.9.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-5h86-8mv2-jq9f 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-5h86-8mv2-jq9f can be triaged on real exposure rather than presence alone.
Tailored to GHSA-5h86-8mv2-jq9f. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
How to detect GHSA-5h86-8mv2-jq9f
A community-maintained Nuclei template exists for this CVE. You can scan for it directly:
nuclei -id ghsa-5h86-8mv2-jq9f -u https://target- Template
- aiohttp - Directory Traversal
- Severity
- high
- Impact
- Unauthenticated attackers can read arbitrary files on the server including sensitive configuration files with credentials and other sensitive data.
- Remediation
- Update aiohttp to version 3.9.2 or later, or disable follow_symlinks option.
Template by ProjectDiscovery nuclei-templates (DhiyaneshDk), MIT licensed. View the full template. Scan only systems you are authorised to test.
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.
This vulnerability has been rated as having a moderate impact. There is a non-default precondition which is required to exploit it: the follow_symlinks setting needs to be enabled.
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat Ansible Automation Platform 2.4 for RHEL 8 | automation-controller-0:4.5.5-2.el8ap | RHSA-2024:1640 |
| Red Hat Satellite 6.14 for RHEL 8 | python-aiohttp-0:3.9.2-0.1.el8pc | RHSA-2024:1536 |
| Red Hat Satellite 6.15 for RHEL 8 | python-aiohttp-0:3.9.2-1.el8pc | RHSA-2024:2010 |
| RHUI 4 for RHEL 8 | python-aiohttp-0:3.9.2-1.el8ui | RHSA-2024:1878 |
Frequently Asked Questions
Is GHSA-5h86-8mv2-jq9f in your dependencies?
O3 Security finds GHSA-5h86-8mv2-jq9f across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.