CVE-2026-78681EPSS p42.2%
CVE-2026-78681CVE-2026-78681
nltk / nltk
Description
NLTK versions before 3.10.3 use xml.etree.ElementTree to parse XML in multiple modules, which honors entity declarations in document DTDs. Attackers can craft XML payloads with nested entity declarations that expand from hundreds of bytes to megabytes in memory, causing denial of service.
Scoring
| CVSS | 7.5 () |
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| EPSS | 0.52% probability of exploitation · percentile 42.2% · 2026-10-05T12:00:23Z |
| Last modified | 2026-09-01 |