GHSA-5mrq-x3x5-8v8f — jupyter-server
MEDIUMGHSA-5mrq-x3x5-8v8f is a medium-severity (CVSS 6.8) CWE-613 vulnerability in jupyter-server. A fix is available for jupyter-server — see the affected versions and patch details below.
Jupyter Server's Authentication Cookies Remain Valid After Password Reset and Server Restart
Exploitation Status
No confirmed exploitation observed yet
- A successful exploit gives an attacker total control of the affected component, not partial access.
- 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-5mrq-x3x5-8v8f.
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-5mrq-x3x5-8v8f 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 379,145 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
jupyter-serverReal-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 persistent cookie secret vulnerability allows authenticated users to maintain indefinite access even after password changes.
The cookie secret used to sign authentication cookies is stored in a permanent file (~/.local/share/jupyter/runtime/jupyter_cookie_secret) that is never automatically rotated or cleared, allowing stolen or compromised cookies to remain valid indefinitely regardless of password resets.
PoC
- Start a Jupyter server with password authentication:
jupyter server password,jupyter server - Log in with the password and capture the authentication cookie (e.g., just login with a browser).
- Change the password to revoke access:
jupyter server password - Restart the server
- Use the old stolen cookie => remains valid and provides full authenticated access.
Impact
- All jupyter-server deployments using password authentication where security incidents may occur
- Multi-user systems where one user's compromised session should be revocable by administrators
- Shared or public-facing Jupyter servers where credential rotation is a security requirement
- Any deployment where password changes are expected to revoke existing sessions
Patches
Jupyter Server 2.18+
Workaround
rm ~/.local/share/jupyter/runtime/jupyter_cookie_secret
# Then restart the server
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | jupyter-server | all versions | 2.18.0pip install --upgrade 'jupyter-server==2.18.0' |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for jupyter-server, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update jupyter-server to 2.18.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-5mrq-x3x5-8v8f 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-5mrq-x3x5-8v8f can be triaged on real exposure rather than presence alone.
Tailored to GHSA-5mrq-x3x5-8v8f. 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-5mrq-x3x5-8v8f in your dependencies?
O3 Security finds GHSA-5mrq-x3x5-8v8f across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.