CVE-2026-52859Public exploitNetwork attack vector

Editor crash via unterminated terminal cell array

Published Jun 11, 2026 · Updated Jun 11, 2026

Out-of-bounds read in Vim before 9.2.0565 allows attackers to crash the editor via crafted output in a :terminal window. update_snapshot() walks a six-entry cell.chars[] array until NUL, although libvterm omits that terminator when a base character and five combining marks fill every slot. Exploitation requires terminal support and a screen snapshot, such as when the terminal job exits or Terminal-Normal mode begins; the demonstrated consequence is an editor crash.

CVSS severity6.9
Medium
EPSS probability0.30%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Out-of-bounds read in Vim before 9.2.0565 allows attackers to crash the editor via crafted output in a :terminal window. update_snapshot() walks a six-entry cell.chars[] array until NUL, although libvterm omits that terminator when a base character and five combining marks fill every slot. Exploitation requires terminal support and a screen snapshot, such as when the terminal job exits or Terminal-Normal mode begins; the demonstrated consequence is an editor crash.

The record

CVE
CVE-2026-52859
Published
Jun 11, 2026
Updated
Jun 11, 2026
Vendor
Vim
Product
Vim
Classifications
CWE-125, T1499
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 11, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 11, 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=< 9.2.0565

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Vim · Vimversion=< 9.2.0565

Published CVSS scores

8.2NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H
6.9GitHub, Inc.CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:L/SC:N/SI:N/SA: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.

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

No observations available

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

Weakness, pattern, technique

CWE-125Out-of-bounds Read
T1499Endpoint Denial of Service

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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