CVE-2020-3286Network attack vector

Administrative code execution via oversized web requests

Published Jun 18, 2020 · Updated Nov 15, 2024

Stack overflow in Cisco Small Business RV router firmware allows remote authenticated users to execute root code via oversized web requests. Management-interface scripts insufficiently restrict the length of user-supplied request values before copying them into stack buffers. Administrative access is required; the interface is LAN-accessible, optional remote management is disabled by default, and exploitation can execute root code or crash the router.

CVSS severity7.2
High
EPSS probability3.19%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stack overflow in Cisco Small Business RV router firmware allows remote authenticated users to execute root code via oversized web requests. Management-interface scripts insufficiently restrict the length of user-supplied request values before copying them into stack buffers. Administrative access is required; the interface is LAN-accessible, optional remote management is disabled by default, and exploitation can execute root code or crash the router.

The record

CVE
CVE-2020-3286
Published
Jun 18, 2020
Updated
Nov 15, 2024
Vendor
ClamAV
Product
Cisco Small Business RV Series Router Firmware
Classifications
CWE-119, CWE-787, T1210
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Jun 18, 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 vectornetwork
Required privilegesadmin

What is affected?

ClamAV · Cisco Small Business RV Series Router Firmwareversion=n/a

Published CVSS scores

7.2Cisco Systems, Inc.CVSS:3.0/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H/E:X/RL:X/RC:X
7.2NIST NVDCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
9.0NIST NVDAV:N/AC:L/Au:S/C:C/I:C/A:C

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
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-119Improper Restriction of Operations within the Bounds of a Memory Buffer
CWE-787Out-of-bounds Write
T1210Exploitation of Remote Services

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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