# CVE-2026-79675: NLTK before 3.10.3 JVM Argument Injection via Per-Call Options

> Attackers can inject malicious JVM flags via per-call options in NLTK's java function to achieve arbitrary code execution.

- **Severity:** Critical 9.3 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 25 Aug 2026
- **Updated:** 27 Aug 2026
- **Also known as:** DEBIAN-CVE-2026-79675, ECHO-8a7e-a35b-937a, GHSA-m4rf-3fr8-xwx3, MINI-jgg2-5rm8-qmhx, PYSEC-2026-3749, UBUNTU-CVE-2026-79675

## What is CVE-2026-79675?

CVE-2026-79675 is a critical command injection vulnerability in nltk, published on 25 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official 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.

Weakness: CWE-88 (Improper Neutralization of Argument Delimiters in a Command)

## Which versions are affected by CVE-2026-79675?

3 open source packages ship an affected version, including nltk. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `nltk` | PyPI | All versions | 3.10.3 |
| `nltk` | PyPI | All versions | 3.10.3 |
| `nltk` | PyPI | All versions | 3.10.3 |

Products: Nltk Nltk.

## How do I fix CVE-2026-79675?

Upgrade nltk to 3.10.3 or later.

## Is CVE-2026-79675 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-79675 exists.

## Other vulnerabilities in nltk

- [CVE-2026-0848](https://insights.sbomify.com/CVE-2026-0848/): Arbitrary Code Execution in NLTK StanfordSegmenter via Untrusted JAR Loading (critical 10.0)
- [CVE-2025-14009](https://insights.sbomify.com/CVE-2025-14009/): Zip Slip Vulnerability in nltk/nltk Leading to Remote Code Execution (critical 10.0)
- [CVE-2026-78683](https://insights.sbomify.com/CVE-2026-78683/): NLTK before 3.10.0 Remote Code Execution via Unsafe Pickle Deserialization (critical 9.4)
- [CVE-2026-79657](https://insights.sbomify.com/CVE-2026-79657/): NLTK before 3.10.3 Remote Code Execution via Unsafe Pickle Deserialization (critical 9.3)
- [CVE-2026-79674](https://insights.sbomify.com/CVE-2026-79674/): NLTK 3.10.2 Path Traversal via corpus-reader constructors (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-79675 and fix it if it is affected.

What it is: CVE-2026-79675 is a critical command injection vulnerability in nltk, published on 25 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-79675 exists.

Affected packages and fixed versions:
- nltk (PyPI): affected all versions; fixed in 3.10.3
- nltk (PyPI): affected all versions; fixed in 3.10.3
- nltk (PyPI): affected all versions; fixed in 3.10.3

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-79675/ (Markdown: https://insights.sbomify.com/CVE-2026-79675/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-79675
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-79675
- OSV: https://osv.dev/vulnerability/CVE-2026-79675

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-79675/
Summaries are generated and may contain mistakes; the official description above is the record.