NLTK versions before 3.10.0 contain a regular expression denial of service vulnerability in Text.findall() and TokenSearcher.findall() methods that accept user-supplied regular expressions without validation or timeout. Attackers can supply crafted regex patterns that cause catastrophic backtracking, resulting in indefinite CPU saturation and denial of service to all users of the Python process.

There are packages installed that are affected by a vulnerability referenced in the following CVE:

  - NLTK versions before 3.10.0 contain a regular expression denial of service vulnerability in Text.findall()
    and TokenSearcher.findall() methods that accept user-supplied regular expressions without validation or
    timeout. Attackers can supply crafted regex patterns that cause catastrophic backtracking, resulting in
    indefinite CPU saturation and denial of service to all users of the Python process. (CVE-2026-80205)

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - NLTK versions before 3.10.0 contain a regular expression denial of service vulnerability in Text.findall()     and TokenSearcher.findall() methods that accept user-supplied regular expressions without validation or     timeout. Attackers can supply crafted regex patterns that cause catastrophic backtracking, resulting in     indefinite CPU saturation and denial of service to all users of the Python process. (CVE-2026-80205)

Note that Nessus relies on the presence of the package as reported by the vendor.

ID	Name	Product	Family	Type	Severity
465504	Echo: nltk: security update to 3.10.0	Tenable Cloud Security	Echo Local Security Checks	Local	high
465504	Echo: nltk: security update to 3.10.0	Tenable Self-Hosted Container Security	Echo Local Security Checks	Local	high
340823	Linux Distros Unpatched Vulnerability : CVE-2026-80205	Nessus	Misc.	Local	high

Detections

Analytics

CVE-2026-80205

high

Tenable Plugins

high

high

high