CVE-2023-4733Public exploit

Process crash via stale window pointer dereference

Published Sep 4, 2023 · Updated Jun 23, 2026

Use-after-free in Vim before 9.0.1840 allows context-dependent attackers to cause a crash via a crafted script-mode file. In do_ecmd, reset_VIsual can run a ModeChanged autocommand that frees oldwin, after which buflist_altfpos dereferences the stale window pointer. Exploitation requires a user to run untrusted input in script mode; the demonstrated consequence is a Vim process crash.

CVSS severity7.3
High
EPSS probability0.54%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Use-after-free in Vim before 9.0.1840 allows context-dependent attackers to cause a crash via a crafted script-mode file. In do_ecmd, reset_VIsual can run a ModeChanged autocommand that frees oldwin, after which buflist_altfpos dereferences the stale window pointer. Exploitation requires a user to run untrusted input in script mode; the demonstrated consequence is a Vim process crash.

The record

CVE
CVE-2023-4733
Published
Sep 4, 2023
Updated
Jun 23, 2026
Vendor
Vim
Product
Vim
Classifications
CWE-416, T1204.002
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 4, 2023CVE publishedPublication date reported by the CVE source.
  2. Jun 23, 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 <9.0.1840

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Vim · Vimversion=unspecified <9.0.1840

Published CVSS scores

7.3huntr.devCVSS:3.0/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H
7.8NIST NVDCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-416Use After Free
T1204.002User Execution: Malicious File

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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