CVE-2021-1289Network attack vector

Root command execution via unvalidated Authorization header

Published Feb 4, 2021 · Updated Nov 12, 2024

Code execution in Cisco Small Business RV Series Router Firmware before 1.0.01.02 allows remote attackers to run arbitrary code as root. The HTTPS web service on TCP port 443 passes an attacker-controlled Authorization header to a system call without validating the string. Authentication is not required, and successful exploitation executes commands with root privileges on the router.

CVSS severity9.8
Critical
EPSS probability4.24%
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 Cisco Small Business RV Series Router Firmware before 1.0.01.02 allows remote attackers to run arbitrary code as root. The HTTPS web service on TCP port 443 passes an attacker-controlled Authorization header to a system call without validating the string. Authentication is not required, and successful exploitation executes commands with root privileges on the router.

The record

CVE
CVE-2021-1289
Published
Feb 4, 2021
Updated
Nov 12, 2024
Vendor
ClamAV
Product
Cisco Small Business RV Series Router Firmware
Classifications
CWE-472, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 4, 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 privilegesunauthenticated

What is affected?

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

Published CVSS scores

9.8Cisco Systems, Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:X/RL:X/RC:X
10.0NIST NVDAV:N/AC:L/Au:N/C:C/I:C/A:C
8.8Trend Micro Zero Day InitiativeCVSS:3.0/AV:A/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.

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 exploitUnconfirmed

Weakness, pattern, technique

CWE-472External Control of Assumed-Immutable Web Parameter
T1190Exploit Public-Facing Application

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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