
CVE catalog
CVE-2026-0848
NLTK versions <=3.9.2 are vulnerable to arbitrary code execution due to improper input validation in the StanfordSegmenter module. The module dynamically loads external Java .jar files without verific
- Severity
- Critical · CVSS 10
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H - Published
- Source
- [NVD] · [CVE record]
- EPSS
- 0.79% · Oct 25, 2026
NLTK versions <=3.9.2 are vulnerable to arbitrary code execution due to improper input validation in the StanfordSegmenter module. The module dynamically loads external Java .jar files without verification or sandboxing. An attacker can supply or replace the JAR file, enabling the execution of arbitrary Java bytecode at import time. This vulnerability can be exploited through methods such as model poisoning, MITM attacks, or dependency poisoning, leading to remote code execution. The issue arises from the direct execution of the JAR file via subprocess with unvalidated classpath input, allowing malicious classes to execute when loaded by the JVM.
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Debian | nltk | sid | 3.10.3-1 | fixed |
| Debian | nltk | forky | 3.10.3-1 | fixed |
| Debian | nltk | trixie | 3.9.1-2 | vulnerable |
| Debian | nltk | bookworm | 3.8-1 | vulnerable |
| Cpe | nltk | Not reported | Not reported | vulnerable |
| Cpe | nltk | Not reported | 3.8.1-1ubuntu0.1~esm2 | fixed |
| Cpe | python3-nltk | Not reported | 3.8.1-1ubuntu0.1~esm2 | fixed |
Fixed-version evidence
| Distribution | Package | Type | Release | Fixed version | Urgency | Origin | Bugs |
|---|---|---|---|---|---|---|---|
| Debian | nltk | source | sid | 3.9.3-1 | not yet assigned | Not reported | Not reported |
| Debian | nltk | source | forky | 3.9.3-1 | not yet assigned | Not reported | Not reported |
| Debian | nltk | source | trixie | (unfixed) | not yet assigned | Not reported | Not reported |
| Debian | nltk | source | bookworm | (unfixed) | not yet assigned | Not reported | Not reported |
| Cpe | nltk | cpe | Not reported | 3.8.1-1ubuntu0.1~esm2 | Not reported | Not reported | Not reported |
| Cpe | python3-nltk | cpe | Not reported | 3.8.1-1ubuntu0.1~esm2 | Not reported | Not reported | Not reported |
Notes
[trixie] nltk: Minor issue [bookworm] nltk: Minor issue
OpenFactory catalog packages
[Debian 12 (Bookworm)]
- [python3-nltk]Affected
Source package: [nltk]
Details (2)
3.8-1· all · bookwormAffected
nvd · nltk · debian · bookworm; nvd · nltk · debian · 12
3.8-1· all · bookwormAffected
nvd · nltk · debian · bookworm; nvd · nltk · debian · 12
[Debian 13 (Trixie)]
- [python3-nltk]Affected
Source package: [nltk]
Details (2)
3.9.1-2· all · trixieAffected
nvd · nltk · debian · 13
3.9.1-2· all · trixieAffected
nvd · nltk · debian · 13
Observed:
References
- [https://nvd.nist.gov/vuln/detail/CVE-2026-0848]
- [https://osv.dev/vulnerability/DEBIAN-CVE-2026-0848]
- [https://security-tracker.debian.org/tracker/CVE-2026-0848]
- [https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-0848.json]
- [https://ubuntu.com/security/notices/USN-8302-1]
[Debian Security Tracker] · [FIRST EPSS] · [National Vulnerability Database (NVD)] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX] · [Ubuntu Security Notices (USN)]