Dashboard / CVE-2026-12372

CVE-2026-12372

LOW
INFO Priority: 0.01 BB Relevance: 57/100
Published: 2026-08-09 Modified: 2026-10-23 First seen: 2026-10-29 Status: active

Attack Surface

Network No Auth No Interaction

CVSS Vector Breakdown

AV: Network
AC: High
PR: None
UI: None
S: Unchanged
C: Low
I: None
A: None

Description

A Server-Side Request Forgery (SSRF) vulnerability exists in nltk/nltk versions 3.9.4 and the current develop branch. The `nltk.pathsec.validate_network_url()` function, intended to prevent SSRF by rejecting internal network addresses, fails to reject IPs in the RFC 6598 shared address space (`100.64.0.0/10`). This occurs because Python's `ipaddress` module does not classify such addresses as `is_private` or `is_global`, and the current guard only checks `is_private` and a few explicit categories. An attacker who can influence a URL passed to NLTK's network-loading helpers can exploit this vulnerability to make a strict-mode application send requests to shared-address-space hosts, potentially exposing non-public infrastructure reachable from the application host. The impact is limited to SSRF-style confidentiality exposure, with no code execution claimed.

Weakness Classification (1)

Affected Software (1)

VendorProductVersion
nltk nltk 3.9.4

References & Advisories (1)

Bug Bounty Relevance

57 / 100
✓ Network accessible
✓ No authentication
✓ No user interaction

CVSS Score

3.7 / 10.0 v3.0
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N

EPSS — Exploitation Probability

0.26%
Raw Score 0.002600
Percentile 17.7%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00260
2026-10-28
0.00260

Intelligence Sources

nvd ref →

External Links