Vulnerability · Published Aug 22, 2026 · Assigned by VulnCheck
CVE-2026-62388NLTK before 3.10.0 Insecure Default Configuration in pathsec.py
High 7.5
In plain English
A high-severity security flaw in nltk from nltk. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 44% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 3.1)7.5High
Exploit odds (30 days)0.5%top 56.1% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known
Official description
NLTK versions before 3.10.0 default to ENFORCE=False in pathsec.py, causing all security validation functions to emit warnings instead of raising exceptions. Attackers can bypass path traversal and pickle deserialization protections by exploiting the disabled security controls that are only active when manually enabled.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | nltk | no fix listed | DEBIAN-CVE-2026-62388 |
| Debian:13 | nltk | no fix listed | DEBIAN-CVE-2026-62388 |
| Debian:14 | nltk | 3.10.0-1 | DEBIAN-CVE-2026-62388 |
| PyPI | nltk | 3.10.0 | GHSA-p3m8-78j2-g5p3 |
| PyPI | nltk | 3.10.0 | PYSEC-2026-3722 |
| Ubuntu:26.10 | nltk | no fix listed | UBUNTU-CVE-2026-62388 |
Affected products (as reported)
Weakness: CWE-1188 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
References
- GitHub Security Advisory (GHSA-p3m8-78j2-g5p3) vendor-advisory
- VulnCheck Advisory: NLTK before 3.10.0 Insecure Default Configuration pathsec third-party-advisory