CVE-2023-0909Public exploit

Local crash via large directory comparison

Published Feb 18, 2023 · Updated Aug 2, 2024

Denial of service in Notepad-- 1.22 allows local users to crash the editor by comparing a directory containing thousands of files. The Directory Comparison Handler enters slow comparison mode on an rclone-mounted tree and processes tens of thousands of compiled files until the NDD process exits without producing a crash report. The reported case requires a local low-privileged user running an unregistered build on Windows 11; the crash closes the editor and discards open temporary editing files.

CVSS severity5.5
Medium
EPSS probability0.27%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Denial of service in Notepad-- 1.22 allows local users to crash the editor by comparing a directory containing thousands of files. The Directory Comparison Handler enters slow comparison mode on an rclone-mounted tree and processes tens of thousands of compiled files until the NDD process exits without producing a crash report. The reported case requires a local low-privileged user running an unregistered build on Windows 11; the crash closes the editor and discards open temporary editing files.

The record

CVE
CVE-2023-0909
Published
Feb 18, 2023
Updated
Aug 2, 2024
Vendor
cxasm
Product
Notepad--
Classifications
CWE-404, T1499.004
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 18, 2023CVE publishedPublication date reported by the CVE source.
  2. Aug 2, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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  1. Affected versionversion=1.22

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

cxasm · Notepad--version=1.22

Published CVSS scores

1.7VulDBAV:L/AC:L/Au:S/C:N/I:N/A:P
3.3VulDBCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

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 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-404Improper Resource Shutdown or Release
T1499.004Endpoint Denial of Service: Application or System Exploitation

Public exploit references

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Technologies

Your stack

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Your stack

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