USN-7365-1: NLTK vulnerabilities

24 March 2025

Several security issues were fixed in NLTK.

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Releases

Packages

  • nltk - Natural Language Toolkit

Details

It was discovered that NLTK contained a regex that is susceptible to
catastrophic backtracking. An attacker could possibly use this issue to
cause a denial of service. (CVE-2021-3842, CVE-2021-43854)

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Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines.

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Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 20.04
Ubuntu 18.04
Ubuntu 16.04
Ubuntu 14.04

In general, a standard system update will make all the necessary changes.

References

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Further reading