CVE-2022-3520Public exploit

Memory corruption via negative Visual-block put column

Published Dec 2, 2022 · Updated Apr 23, 2025

Heap-based buffer overflow in Vim before 9.0.0765 allows local users to corrupt memory through crafted Visual-block put commands. The do_put function in src/register.c calculates an operation-end column that can become negative and uses it without first clamping it to zero. A user must execute the crafted editing sequence; the upstream regression demonstrates a process crash, and stronger consequences are not publicly demonstrated.

CVSS severity7.8
High
EPSS probability1.03%
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 9.0.0765 allows local users to corrupt memory through crafted Visual-block put commands. The do_put function in src/register.c calculates an operation-end column that can become negative and uses it without first clamping it to zero. A user must execute the crafted editing sequence; the upstream regression demonstrates a process crash, and stronger consequences are not publicly demonstrated.

The record

CVE
CVE-2022-3520
Published
Dec 2, 2022
Updated
Apr 23, 2025
Vendor
Vim
Product
Vim
Classifications
CWE-122, T1204.002
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 2, 2022CVE publishedPublication date reported by the CVE source.
  2. Apr 23, 2025Record 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 <9.0.0765

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Vim · Vimversion=unspecified <9.0.0765

Published CVSS scores

7.8huntr.dev CNACVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
7.8Amazon LinuxCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
9.8NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/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-122Heap-based Buffer Overflow
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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