Affected: Homebrew: acronym

## Vulnerability

The fix for CVE-2026-12841 (CWE-88, JVM argument injection) added `_validate_java_options()` to block dangerous JVM flags such as `-agentlib`, `-agentpath`, `-javaagent`, `-Xrunjdwp`, and `@argfile` references. However, the validation is only applied when setting global options via `config_java()`. The `java()` function's per-call `options` parameter -- added by PR #3683 (CVE-2026-12615 fix) -- passes options directly to `subprocess.Popen` without calling `_validate_java_options()`.

All four Stanford Java wrapper classes accept user-supplied `java_options` and route them through the unvalidated per-call path, bypassing the CVE-2026-12841 fix entirely.

## Root Cause

In `nltk/internals.py`, the `java()` function (line 128) accepts an `options` keyword argument. When `options` is not None, it is converted to a list and prepended to the JVM command (lines 211-217) without any validation:

```python # nltk/internals.py, lines 211-217 (HEAD) if options is None: java_options = _java_options # validated by config_java() else: if isinstance(options, str): options = options.split() java_options = list(options) # NO validation cmd = [_java_bin] + java_options + cmd ```

Compare with `config_java()` (line 92) which does validate:

```python # nltk/internals.py, lines 122-123 _validate_java_options(options) _java_options[:] = options ```

The four affected wrapper classes store user-supplied `java_options` without validation and pass t…

NLTK before 3.10.3 fails to validate JVM options passed through the per-call options parameter in the java() function, allowing attackers to inject dangerous JVM flags. Attackers can supply malicious options like -agentpath, -javaagent, or @argfile to Stanford wrapper classes to achieve arbitrary code execution.

Withdrawn by the publisher.

Affected: PyPI: nltk

## Duplicate Advisory

This advisory has been withdrawn because it is a duplicate of GHSA-m4rf-3fr8-xwx3. This link is maintained to preserve external references.

## Original Description

NLTK before 3.10.3 fails to validate JVM options passed through the per-call options parameter in the java() function, allowing attackers to inject dangerous JVM flags. Attackers can supply malicious options like -agentpath, -javaagent, or @argfile to Stanford wrapper classes to achieve arbitrary code execution.

Affected: PyPI: nltk

NLTK before 3.10.3 fails to validate JVM options passed through the per-call options parameter in the java() function, allowing attackers to inject dangerous JVM flags. Attackers can supply malicious options like -agentpath, -javaagent, or @argfile to Stanford wrapper classes to achieve arbitrary code execution.

Affected: Ubuntu:Pro:14.04:LTS: nltk, Ubuntu:Pro:16.04:LTS: nltk, Ubuntu:Pro:18.04:LTS: nltk, Ubuntu:Pro:20.04:LTS: nltk, Ubuntu:Pro:22.04:LTS: nltk, Ubuntu:Pro:24.04:LTS: nltk, Ubuntu:Pro:26.04:LTS: nltk

NLTK before 3.10.3 fails to validate JVM options passed through the per-call options parameter in the java() function, allowing attackers to inject dangerous JVM flags. Attackers can supply malicious options like -agentpath, -javaagent, or @argfile to Stanford wrapper classes to achieve arbitrary code execution.