{"id":"GHSA-pv39-qrfq-g8gc","summary":"Duplicate Advisory: NLTK: Missing Post-Download Integrity Verification Allows Malicious Package Injection","details":"## Duplicate Advisory\n\nThis advisory has been withdrawn because it is a duplicate of GHSA-5wp5-5229-5g6q. This link is maintained to preserve external references.\n\n## Original Description\nIn nltk version 3.9.4, the `nltk.downloader.Downloader._download_package()` function writes downloaded package bytes to disk and may extract them before enforcing SHA-256 or MD5 checksum validation. This allows an attacker to tamper with the package response body for `info.url` through a compromised mirror, malicious proxy, or other source-substitution condition, leading to the installation of attacker-controlled package bytes. The vulnerability can result in malicious corpus or model content being trusted by downstream users or applications.","modified":"2026-09-01T20:45:05.623447439Z","published":"2026-08-03T09:32:37Z","withdrawn":"2026-09-01T20:30:34Z","database_specific":{"nvd_published_at":"2026-08-03T08:17:17Z","cwe_ids":["CWE-494"],"severity":"MODERATE","github_reviewed":true,"github_reviewed_at":"2026-09-01T20:30:34Z"},"references":[{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-12259"},{"type":"WEB","url":"https://huntr.com/bounties/659ccf6d-12d4-4d4a-84c0-078633c35a5d"}],"affected":[{"package":{"name":"nltk","ecosystem":"PyPI","purl":"pkg:pypi/nltk"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"3.9.2"}]}],"versions":["0.8","0.9","0.9.3","0.9.4","0.9.5","0.9.6","0.9.7","0.9.8","0.9.9","2.0.1","2.0.1rc1","2.0.1rc2-git","2.0.1rc3","2.0.1rc4","2.0.2","2.0.3","2.0.4","2.0.5","2.0b4","2.0b5","2.0b6","2.0b7","2.0b8","2.0b9","3.0.0","3.0.0b1","3.0.0b2","3.0.1","3.0.2","3.0.3","3.0.4","3.0.5","3.1","3.2","3.2.1","3.2.2","3.2.3","3.2.4","3.2.5","3.3","3.4","3.4.1","3.4.2","3.4.3","3.4.4","3.4.5","3.5","3.5b1","3.6","3.6.1","3.6.2","3.6.3","3.6.4","3.6.5","3.6.6","3.6.7","3.7","3.8","3.8.1","3.9","3.9.1","3.9.2","3.9b1"],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/08/GHSA-pv39-qrfq-g8gc/GHSA-pv39-qrfq-g8gc.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.0/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N"}]}