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CVE-2023-20118Exploited in the wildNVD status: Analyzed

Cisco Small Business RV Series Routers Command Injection

CVE-2023-20118 is a high-severity improper neutralization of special elements used in a command vulnerability in Cisco Small Business RV Series Router Firmware from Cisco, with a CVSS 3.1 base score of 7.2 out of 10. It can be exploited remotely over the network by an attacker with administrator privileges, without any action from a user. Affected Cisco Small Business RV Series Router Firmware versions: 1.0.1.17; 1.0.2.03; 1.1.0.09, and others listed below. The record does not name a fixed version, so check the vendor advisory. CISA added it to the Known Exploited Vulnerabilities catalogue on March 3, 2025, which means attacks have been observed in the wild.

Patch now

Attackers are already exploiting this vulnerability, according to CISA.

What to do

  1. Check which version of Cisco Small Business RV Series Router Firmware you run against the affected versions below, and install the vendor's latest release.
  2. CISA's required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
  3. Read the advisory on sec.cloudapps.cisco.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
CiscoCisco Small Business RV Series Router Firmware1.0.1.17; 1.0.2.03; 1.1.0.09; 1.1.1.19; 1.1.1.06; 1.2.1.13; 1.2.1.14; 1.3.1.12; and 10 more rangesNot stated
CiscoRv016 FirmwareNot specified in the recordNot stated
CiscoRv042 FirmwareNot specified in the recordNot stated
CiscoRv042g FirmwareNot specified in the recordNot stated
CiscoRv082 FirmwareNot specified in the recordNot stated
CiscoRv320 FirmwareNot specified in the recordNot stated
CiscoRv325 FirmwareNot specified in the recordNot stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
HighAdministrator-level access is required first.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.16.5MediumCNA (cisco.com)
CVSS 3.17.2HighNVD

Official description

A vulnerability in the web-based management interface of Cisco Small Business Routers RV016, RV042, RV042G, RV082, RV320, and RV325 Routers could allow an authenticated, remote attacker to execute arbitrary commands on an affected device. This vulnerability is due to improper validation of user input within incoming HTTP packets. An attacker could exploit this vulnerability by sending a crafted HTTP request to the web-based management interface. A successful exploit could allow the attacker to gain root-level privileges and access unauthorized data. To exploit this vulnerability, an attacker would need to have valid administrative credentials on the affected device. Cisco has not and will not release software updates that address this vulnerability. However, administrators may disable the affected feature as described in the Workarounds ["#workarounds"] section. {{value}} ["%7b%7bvalue%7d%7d"])}]]

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Neutralization of Special Elements used in a Command

The product constructs all or part of a command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended command when it is sent to a downstream component.

How developers prevent this class of flaw

  • If at all possible, use library calls rather than external processes to recreate the desired functionality.
  • If possible, ensure that all external commands called from the program are statically created.
  • Run time: Run time policy enforcement may be used in an allowlist fashion to prevent use of any non-sanctioned commands.

More Improper Neutralization of Special Elements used in a Command vulnerabilities (CWE-77)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: active, automatable: no, technical impact: total).
  3. Added to CISA's Known Exploited Vulnerabilities catalogue.
  4. Deadline for US federal agencies to remediate, set by CISA.
  5. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Other vulnerabilities in Cisco Small Business RV Series Router Firmware

All Cisco Small Business RV Series Router Firmware vulnerabilities

Recent Improper Neutralization of Special Elements used in a Command vulnerabilities

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