CVE-2021-1163Network attack vector

Authenticated root code execution via HTTP input validation

Published Jan 13, 2021 · Updated Nov 12, 2024

Improper input validation in Cisco Small Business RV Series Router Firmware allows authenticated remote attackers to execute root code or reload devices. The web-based management interface processes crafted HTTP requests without correctly validating user-supplied input, enabling command execution as root or a forced device reload. Valid administrator credentials are required; Cisco reports no software update and no known public or malicious exploitation, so impact is limited to reachable management interfaces and can be code execution or denial of service.

CVSS severity7.2
High
EPSS probability2.19%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input validation in Cisco Small Business RV Series Router Firmware allows authenticated remote attackers to execute root code or reload devices. The web-based management interface processes crafted HTTP requests without correctly validating user-supplied input, enabling command execution as root or a forced device reload. Valid administrator credentials are required; Cisco reports no software update and no known public or malicious exploitation, so impact is limited to reachable management interfaces and can be code execution or denial of service.

The record

CVE
CVE-2021-1163
Published
Jan 13, 2021
Updated
Nov 12, 2024
Vendor
ClamAV
Product
Cisco Small Business RV Series Router Firmware
Classifications
CWE-787, CWE-121, T1210
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jan 13, 2021CVE publishedPublication date reported by the CVE source.
  2. Nov 12, 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 privilegesauthenticated

What is affected?

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

Published CVSS scores

7.2Cisco Systems, Inc.CVSS: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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-787Out-of-bounds Write
CWE-121Stack-based Buffer Overflow
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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