CVE-2026-6321
7.5 · HIGHOverview
CVE-2026-6321 is a high-severity vulnerability affecting openjsf fast-uri. It was published on May 4, 2026 and has a CVSS 3.1 base score of 7.5 (HIGH).
This vulnerability has a CVSS 3.1 base score of 7.5, rated HIGH. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical Description
fast-uri decoded percent-encoded path separators and dot segments before applying dot-segment removal in its normalize() and equal() functions. Encoded path data was treated like real slashes and parent-directory references, so distinct URIs could collapse onto the same normalized path. Applications that normalize or compare attacker-controlled URLs to enforce path-based policy can be bypassed, with a path that appears confined under an allowed prefix normalizing to a different location. Versions <= 3.1.0 are affected. Update to 3.1.1 or later.
Remediation
Check the references section for vendor advisories and patches from openjsf. Update fast-uri 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
| Vendor | Product | Versions | Status |
|---|---|---|---|
| openjsf | fast-uri | >= 0, < 3.1.1 | Affected |
References
Frequently Asked Questions
What is CVE-2026-6321?
CVE-2026-6321 is a high-severity vulnerability affecting openjsf fast-uri. It was published on May 4, 2026 and has a CVSS 3.1 base score of 7.5 (HIGH).
How severe is CVE-2026-6321?
This vulnerability has a CVSS 3.1 base score of 7.5, rated HIGH. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2026-6321?
Check the references section for vendor advisories and patches from openjsf. Update fast-uri 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-2026-6321?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-6321 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.
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