CVE-2026-66393
7.5 · HIGHOverview
CVE-2026-66393 is a high-severity vulnerability affecting nltk nltk. It was published on August 22, 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
NLTK versions before 3.9.4 contain an unbounded recursion vulnerability in JSONTaggedDecoder.decode_obj() that allows attackers to cause denial of service by supplying deeply nested JSON structures. Attackers can craft JSON payloads exceeding the recursion limit to trigger an unhandled RecursionError that crashes the Python process.
Remediation
Check the references section for vendor advisories and patches from nltk. Update nltk 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 |
|---|---|---|---|
| nltk | nltk | >= 0, < 3.9.4 | Affected |
Frequently Asked Questions
What is CVE-2026-66393?
CVE-2026-66393 is a high-severity vulnerability affecting nltk nltk. It was published on August 22, 2026 and has a CVSS 3.1 base score of 7.5 (HIGH).
How severe is CVE-2026-66393?
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-2026-66393?
Check the references section for vendor advisories and patches from nltk. Update nltk 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-2026-66393?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-66393 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
AI agents map your attack surface to find vulnerabilities like this one.
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