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

[CVE catalog]

Severity
Critical · CVSS 10CVSS: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.

DistributionPackageReleaseVersionStatus
Debiannltksid3.10.3-1fixed
Debiannltkforky3.10.3-1fixed
Debiannltktrixie3.9.1-2vulnerable
Debiannltkbookworm3.8-1vulnerable
CpenltkNot reportedNot reportedvulnerable
CpenltkNot reported3.8.1-1ubuntu0.1~esm2fixed
Cpepython3-nltkNot reported3.8.1-1ubuntu0.1~esm2fixed

Fixed-version evidence

DistributionPackageTypeReleaseFixed versionUrgencyOriginBugs
Debiannltksourcesid3.9.3-1not yet assignedNot reportedNot reported
Debiannltksourceforky3.9.3-1not yet assignedNot reportedNot reported
Debiannltksourcetrixie(unfixed)not yet assignedNot reportedNot reported
Debiannltksourcebookworm(unfixed)not yet assignedNot reportedNot reported
CpenltkcpeNot reported3.8.1-1ubuntu0.1~esm2Not reportedNot reportedNot reported
Cpepython3-nltkcpeNot reported3.8.1-1ubuntu0.1~esm2Not reportedNot reportedNot 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 · bookworm

      Affected

      nvd · nltk · debian · bookworm; nvd · nltk · debian · 12

    • 3.8-1 · all · bookworm

      Affected

      nvd · nltk · debian · bookworm; nvd · nltk · debian · 12

[Debian 13 (Trixie)]

  • [python3-nltk]Affected

    Source package: [nltk]

    Details (2)
    • 3.9.1-2 · all · trixie

      Affected

      nvd · nltk · debian · 13

    • 3.9.1-2 · all · trixie

      Affected

      nvd · nltk · debian · 13

Observed:

References