CVE-2021-47663

HIGH

Published Apr 24, 2025 Modified Apr 15, 2026 CWE-613

Description

Due to improper JSON Web Tokens implementation an unauthenticated remote attacker can guess a valid session ID and therefore impersonate a user to gain full access.

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CVSS v3.1 Score

8.1

HIGH

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Weakness Type (CWE)

CWE-613 CWE-613

References

Other References

https://www.sciencedirect.com/science/article/pii/S2351978921001657

Frequently Asked Questions

What is CVE-2021-47663? +

Due to improper JSON Web Tokens implementation an unauthenticated remote attacker can guess a valid session ID and therefore impersonate a user to gain full access. It has a CVSS v3.1 base score of 8.1 (HIGH).

How severe is CVE-2021-47663? +

CVE-2021-47663 has a CVSS v3.1 score of 8.1 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

How do I check if I'm vulnerable to CVE-2021-47663? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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