Withdrawn: this CVE is not a vulnerability
The assigning CNA withdrew CVE-2026-63310 on 16 October 2026, and it carries the Rejected state at CVE.org and NVD. It must not be treated as a live finding. Its pre-withdrawal severity, score and exploitability are withheld below; the record itself is kept because withdrawals are reversible and because the reject reason is the correction worth publishing.
CVE-2026-63310
NLTK before 3.9.3 Missing Post-Download Integrity Verification
Description
Rejected reason: This CVE ID has been rejected or withdrawn by its CVE Numbering Authority.
INFO
Published Date :
Aug. 22, 2026, 3:16 p.m.
Last Modified :
Oct. 16, 2026, 3:10 p.m.
Remotely Exploit :
—
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | HIGH | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 3.1 | HIGH | [email protected] | ||||
| CVSS 3.1 | HIGH | MITRE-CVE | ||||
| CVSS 3.1 | MEDIUM | [email protected] | ||||
| CVSS 4.0 | CRITICAL | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 4.0 | CRITICAL | [email protected] |
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
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The following list is the news that have been mention
CVE-2026-63310 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-63310 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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CVE Translated by [email protected]
Oct. 16, 2026
Action Type Old Value New Value Changed Translation Title: rechazado, Description: Motivo del rechazo: Este ID de CVE ha sido rechazado o retirado por su Autoridad de Numeración de CVE (CNA). Title: rechazado, Description: Motivo del rechazo: Este ID de CVE ha sido rechazado o retirado por su Autoridad de Numeración de CVE (CNA). -
CVE Translated by [email protected]
Oct. 15, 2026
Action Type Old Value New Value Added Translation Title: rechazado, Description: Motivo del rechazo: Este ID de CVE ha sido rechazado o retirado por su Autoridad de Numeración de CVE (CNA). -
CVE Rejected by [email protected]
Sep. 15, 2026
Action Type Old Value New Value -
CVE Modified by [email protected]
Sep. 15, 2026
Action Type Old Value New Value Changed 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. Rejected reason: This CVE ID has been rejected or withdrawn by its CVE Numbering Authority. Removed CVSS V4.0 VulnCheck: AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Removed CVSS V3.1 VulnCheck: AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:H/A:H Removed CVSS V3.1 NIST: AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:N Removed CWE VulnCheck: CWE-494 Removed CPE Configuration OR *cpe:2.3:a:nltk:nltk:*:*:*:*:*:*:*:* versions up to (excluding) 3.9.3 Added Affected Affected value removed. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/63xxx/CVE-2026-63310.json">CVE-2026-63310</a> Removed Reference VulnCheck: https://github.com/nltk/nltk/security/advisories/GHSA-5wp5-5229-5g6q Removed Reference VulnCheck: https://www.vulncheck.com/advisories/nltk-before-missing-post-download-integrity-verification Removed Reference Type VulnCheck: https://github.com/nltk/nltk/security/advisories/GHSA-5wp5-5229-5g6q Types: Exploit, Vendor Advisory Removed Reference Type VulnCheck: https://www.vulncheck.com/advisories/nltk-before-missing-post-download-integrity-verification Types: Third Party Advisory -
Initial Analysis by [email protected]
Aug. 31, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:N Added CPE Configuration OR *cpe:2.3:a:nltk:nltk:*:*:*:*:*:*:*:* versions up to (excluding) 3.9.3 Added Reference Type VulnCheck: https://github.com/nltk/nltk/security/advisories/GHSA-5wp5-5229-5g6q Types: Exploit, Vendor Advisory Added Reference Type VulnCheck: https://www.vulncheck.com/advisories/nltk-before-missing-post-download-integrity-verification Types: Third Party Advisory -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Aug. 24, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-63310', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'no'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-08-24T19:05:46.890115Z'} -
New CVE Received by [email protected]
Aug. 22, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'nltk', 'product': 'nltk', 'versions': [{'status': 'affected', 'version': '0', 'lessThan': '3.9.3', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '3.9.3', 'versionType': 'semver'}], 'packageURL': 'pkg:pypi/nltk', 'defaultStatus': 'unaffected'}] Added 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. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CVSS V3.1 AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:H/A:H Added CWE CWE-494 Added Reference https://github.com/nltk/nltk/security/advisories/GHSA-5wp5-5229-5g6q Added Reference https://www.vulncheck.com/advisories/nltk-before-missing-post-download-integrity-verification