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.
This CVE has been withdrawn by MITRE
MITRE marked CVE-2026-63310 as REJECTED on . It is no longer considered a valid vulnerability record. The original content below is preserved for historical reference only.
Reason given by MITRE
This CVE ID has been rejected or withdrawn by its CVE Numbering Authority.
CVE-2026-63310
✕ Withdrawn — historical dataMEDIUMNVD 6.5
6.5CVSS
- CVSS v3
- 6.5
- EchelonGraph score
- Not yet assessedThis CVE record was withdrawn by its numbering authority, so there is no vulnerability to rate.
- EPSS PROB
- —
- EPSS %ILE
- —
- KEV
- —Not applicable: this CVE ID was withdrawn
Published
August 22, 2026
Last Modified
August 31, 2026
References (2)
Frequently asked(4)
What is CVE-2026-63310?
CVE-2026-63310 is a rejected CVE ID: its record was withdrawn on September 14, 2026 and no longer describes a vulnerability. Reason given: This CVE ID has been rejected or withdrawn by its CVE Numbering Authority.
When was the CVE record for CVE-2026-63310 published?
The CVE record for CVE-2026-63310 was published on August 22, 2026. EchelonGraph's copy of the record carries a last-modified date of August 31, 2026; the record at its source may have been updated since.
What is the CVSS score of CVE-2026-63310?
CVE-2026-63310 has a CVSS v3 base score of 6.5 (NVD).
How do I remediate CVE-2026-63310?
There is nothing to remediate under CVE-2026-63310: it is a rejected (withdrawn) CVE ID and no longer describes a vulnerability.