CVE-2026-0846Public exploitNetwork attack vector

Arbitrary file read via unrestricted filestring path

Published Mar 9, 2026 · Updated Mar 9, 2026

Absolute path traversal in nltk.util.filestring() in NLTK 3.9.2 allows attackers to read local files via crafted path input. The function passes any string argument directly to Python's open() and returns the file contents without restricting the path to an allowed directory. Exploitation requires an application or local caller to pass attacker-controlled input to filestring(); remote exposure exists only when a service does so.

CVSS severity8.6
High
EPSS probability0.43%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Absolute path traversal in nltk.util.filestring() in NLTK 3.9.2 allows attackers to read local files via crafted path input. The function passes any string argument directly to Python's open() and returns the file contents without restricting the path to an allowed directory. Exploitation requires an application or local caller to pass attacker-controlled input to filestring(); remote exposure exists only when a service does so.

The record

CVE
CVE-2026-0846
Published
Mar 9, 2026
Updated
Mar 9, 2026
Vendor
NLTK Project
Product
NLTK
Classifications
CWE-36, CWE-22, T1005
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 9, 2026CVE publishedPublication date reported by the CVE source.
  2. Mar 9, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=unspecified <=latest

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

NLTK Project · NLTKversion=unspecified <=latest

Published CVSS scores

8.6huntr.devCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:L
7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
7.5redhat-SADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-36Absolute Path Traversal
CWE-22Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
T1005Data from Local System

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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