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CVE-2026-63310

CriticalCVSS 9.3 / 10
Published Aug 22, 2026·Last modified Aug 23, 2026
Affected Components(38)
nltk/nltk
3.6.2
nltk/nltk
3.6.5
nltk/nltk
3.0.2
1 / 13
Description

NLTK before 3.9.3 fails to verify file integrity after downloading packages and before extraction in the downloader module. Attackers can perform man-in-the-middle attacks or DNS poisoning to inject malicious package contents that are extracted without validation.

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Risk Scores
Base Score
9.3

The vulnerability can be exploited over the network without needing physical access. It is easy for an attacker to exploit this vulnerability. An attacker does not need any special privileges or access rights. No user interaction is needed for the attacker to exploit this vulnerability.

Threat Intelligence
8.1

Exploitation activity has been observed. Apply available patches or mitigations urgently.

EPSS
N/A

Probability that this vulnerability will be exploited in the wild within the next 30 days.

Exploit
Not available

We did not find any exploit available. Neither in GitHub repositories nor in the Exploit-Database.

Related Vulnerabilities
  • EUVD-2026-52226
    Alias
  • CVE-2026-12259
    Alias
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