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CVE Record

CVE-2021-1333: Cisco Small Business RV Series Routers Management Interface Remote Command Execution and Denial of Service Vulnerabilities

Multiple vulnerabilities in the web-based management interface of Cisco Small Business RV016, RV042, RV042G, RV082, RV320, and RV325 Routers could allow an authenticated, remote attacker to execute arbitrary code or cause an affected device to restart unexpectedly. These vulnerabilities are due to improper validation of user-supplied input in the web-based management interface. An attacker could exploit these vulnerabilities by sending crafted HTTP requests to an affected device. A successful exploit could allow the attacker to execute arbitrary code as the root user on the underlying operating system or cause the device to reload, resulting in a denial of service (DoS) condition. To exploit these vulnerabilities, an attacker would need to have valid administrator credentials on the affected device.

HighCVSS 7.2Not KEV-listedUpdated
Glexia's TakeAutomated analysishigh

Security readout for executives and security teams

Plain-English summary

This flaw affects several Cisco Small Business RV routers. An attacker who already has valid administrator credentials could use the web management interface to run code as root or force the router to restart, potentially disrupting network access or compromising the device.

Executive priority

Prioritize remediation for affected routers that support business connectivity or remote sites. The flaw needs administrator credentials, but successful exploitation could fully compromise the router or disrupt availability.

Technical view

CVE-2021-1333 is an authenticated remote command execution and denial-of-service issue in the web-based management interface of Cisco RV016, RV042, RV042G, RV082, RV320, and RV325 routers. Cisco attributes it to improper validation of user input. CVSS 3.1 is 7.2, high severity, with high privileges required.

Likely exposure

Exposure is most likely where affected Cisco Small Business RV routers are still deployed and administrator access to the web management interface is available. The source bundle does not provide affected firmware ranges.

Exploitation context

The sources state exploitation requires valid administrator credentials and crafted HTTP requests to the management interface. The CVE is not listed as KEV in the bundle, and no cited source states active exploitation.

Researcher notes

The bundle identifies CWE-121 and improper input validation in the management interface, but does not include firmware version granularity, exploit telemetry, or detailed fixed-release data. Treat vendor advisory review as required before final remediation planning.

Mitigation direction

  • Review Cisco’s advisory for affected firmware and fixed-release guidance.
  • Inventory RV016, RV042, RV042G, RV082, RV320, and RV325 devices.
  • Limit router administrator access to trusted management paths.
  • Audit administrator accounts because exploitation requires valid admin credentials.
  • Monitor for unexpected device reloads or suspicious admin activity.

Validation and detection

  • Identify all deployed Cisco Small Business RV Series routers.
  • Compare each device model and firmware against Cisco’s advisory.
  • Confirm web management access is not broadly reachable.
  • Review logs for unexpected reloads and administrator sessions.
  • Check whether administrative credentials have been shared or reused.
Prepared
Confidence
medium
Sources
3

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.

cwe · low confidence lookup

CWE-121: Exact CWE lookup

Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.

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description · low confidence lookup

Execution behavior lookup

The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.

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cve · low confidence lookup

CVE-2021-1333 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

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Vulnerability profileCVE Program record
Severity
High
CVSS
7.2 (3.1)
Known Exploited
No
Published

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

Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

1CVSS vectors
0Timeline events
0ADP providers
2Source links

CVSS vector scores

1 official score

We collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.

ScoreVersionSeverityVectorExploitImpactSource
7.2CVSS 3.1HighCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H1.25.9Primary CVE score

Vulnerability scoring details

Base CVSS 3.1 score

7.2High
CVSS 3.1 vector shape for CVE-2021-1333Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

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

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Privileges Required
NoneLowHigh
User Interaction
NoneRequired
Scope
ChangedUnchanged
Confidentiality Impact
HighLowNone
Integrity Impact
HighLowNone
Availability Impact
HighLowNone
Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
CiscoCisco Small Business RV Series Router Firmwaren/aListed
Weakness

CWE details

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.

CWE-121 · source CWE mapping

Stack-based Buffer Overflow

Stack-based Buffer Overflow represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.