CVE-2023-4781Public exploit

Code execution via text-locked window exchange

Published Sep 5, 2023 · Updated Jun 23, 2026

Heap-based buffer overflow in Vim before 9.0.1873 allows local users to crash the editor or execute code through crafted input. During substitution, vim_regsub_both permits a window exchange while text is locked, invalidating buffer state and allowing a negative match count to drive an out-of-bounds heap access. Exploitation requires a user to process crafted input; successful abuse can terminate Vim or execute code in its process.

CVSS severity7.8
High
EPSS probability0.61%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Heap-based buffer overflow in Vim before 9.0.1873 allows local users to crash the editor or execute code through crafted input. During substitution, vim_regsub_both permits a window exchange while text is locked, invalidating buffer state and allowing a negative match count to drive an out-of-bounds heap access. Exploitation requires a user to process crafted input; successful abuse can terminate Vim or execute code in its process.

The record

CVE
CVE-2023-4781
Published
Sep 5, 2023
Updated
Jun 23, 2026
Vendor
Vim
Product
Vim
Classifications
CWE-122, T1204.002
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 5, 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 <9.0.1873

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Vim · Vimversion=unspecified <9.0.1873

Published CVSS scores

7.8NIST NVDCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
7.8huntr.devCVSS:3.0/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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

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

Weakness, pattern, technique

CWE-122Heap-based Buffer Overflow
T1204.002Malicious 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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