CVE-2026-5422
8.1 · HIGHOverview
CVE-2026-5422 is a high-severity vulnerability affecting jupyter jupyter_server. It was published on June 2, 2026 and has a CVSS 3.1 base score of 8.1 (HIGH).
This vulnerability has a CVSS 3.1 base score of 8.1, rated HIGH. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
Technical Description
A path traversal vulnerability exists in jupyter-server version 2.17.0 due to an incorrect root directory boundary check in the _get_os_path() function within jupyter_server/services/contents/fileio.py. The check uses startswith(root) without appending a trailing path separator, allowing sibling directories with names starting with the same prefix as root_dir to bypass the check. Additionally, the to_os_path() function in utils.py does not strip ".." from path parts, enabling traversal sequences to bypass the vulnerable check. This vulnerability can lead to unauthorized read/write access to files in sibling directories, potentially exposing sensitive data in shared hosting environments.
Remediation
Check the references section for vendor advisories and patches from jupyter. Update jupyter_server to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
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Frequently Asked Questions
What is CVE-2026-5422?
CVE-2026-5422 is a high-severity vulnerability affecting jupyter jupyter_server. It was published on June 2, 2026 and has a CVSS 3.1 base score of 8.1 (HIGH).
How severe is CVE-2026-5422?
This vulnerability has a CVSS 3.1 base score of 8.1, rated HIGH. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
How do I fix or remediate CVE-2026-5422?
Check the references section for vendor advisories and patches from jupyter. Update jupyter_server to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-5422?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-5422 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
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