CVE-2020-3258

Admin code execution via diagnostic memory overwrite

Published Jun 3, 2020 · Updated Nov 15, 2024

Code execution in the diagnostic test CLI of Cisco IOS allows local users to run arbitrary code on affected industrial routers. Under specific circumstances, the command's restriction logic permits run-time memory modification, allowing system memory locations to be overwritten. Valid privilege-level-15 credentials and local CLI access are required; successful exploitation executes code without a reported availability impact.

CVSS severity5.7
Medium
EPSS probability4.65%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Code execution in the diagnostic test CLI of Cisco IOS allows local users to run arbitrary code on affected industrial routers. Under specific circumstances, the command's restriction logic permits run-time memory modification, allowing system memory locations to be overwritten. Valid privilege-level-15 credentials and local CLI access are required; successful exploitation executes code without a reported availability impact.

The record

CVE
CVE-2020-3258
Published
Jun 3, 2020
Updated
Nov 15, 2024
Vendor
ClamAV
Product
Cisco IOS
Classifications
CWE-119, T1059.008
Attack vector
local
Privileges
admin

Timeline

How it unfolded

  1. Jun 3, 2020CVE publishedPublication date reported by the CVE source.
  2. Nov 15, 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?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=n/a

What conditions does exploitation require?

Attack vectorlocal
Required privilegesadmin

What is affected?

ClamAV · Cisco IOSversion=n/a

Published CVSS scores

5.7CiscoCVSS:3.0/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A: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.

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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
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-119Improper Restriction of Operations within the Bounds of a Memory Buffer
T1059.008Network Device CLI

Public exploit references

No public exploit references are available in this record.

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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