This page tracks the Debian fix status. The vulnerability itself is described on the main CVE page. View CVE-2026-66393 →

DEBIAN-CVE-2026-66393

NLTK versions before 3.9.4 contain an unbounded recursion vulnerability in JSONTaggedDecoder.decode_obj() that allows attackers to cause denial of ser...

Original description

The description as published by the source.

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.

Source: OSV.dev (Open Source Vulnerabilities) OSV

Affected packages

Debian:12 nltk

[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]

Debian:13 nltk

[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]

Debian:14 nltk

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.10.0-1"}]}]

References

advisory security-tracker.debian.org