Description
A vulnerability in the `filestring()` function of the `nltk.util` module in nltk version 3.9.2 allows arbitrary file read due to improper validation of input paths. The function directly opens files specified by user input without sanitization, enabling attackers to access sensitive system files by providing absolute paths or traversal paths. This vulnerability can be exploited locally or remotely, particularly in scenarios where the function is used in web APIs or other interfaces that accept user-supplied input.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| nltk | nltk/nltk | unspecified – ≤ latest | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | nltk | 3.9.3-1 | — |
| Debian 13 | nltk | No fix yet | — |
| Debian 12 | nltk | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | nltk | No fix yet | — |
| Ubuntu 25.10 | nltk | No fix yet | — |
Show 7 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 26.04 LTS | nltk | 3.9.2-1ubuntu0.1~esm2 | — |
| Ubuntu Pro 24.04 LTS | nltk | 3.8.1-1ubuntu0.1~esm2 | — |
| Ubuntu Pro 22.04 LTS | nltk | 3.7-1ubuntu0.1~esm2 | — |
| Ubuntu Pro 20.04 LTS | nltk | 3.4.5-2ubuntu0.1~esm4 | — |
| Ubuntu Pro 18.04 LTS | nltk | 3.2.5-1ubuntu0.1+esm4 | — |
| Ubuntu Pro 16.04 LTS | nltk | 3.1-1ubuntu0.1+esm4 | — |
| Ubuntu Pro 14.04 LTS | nltk | 2.0~b9-0ubuntu4.1~esm6 | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| PyPI | nltk | < 3.9.3 | 3.9.3 | GHSA-h8wq-7xc4-p3qx |
| PyPI | nltk | <= 3.9.2 | — | PYSEC-2026-97 |