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CVE Record

CVE-2021-1331: 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

CVE-2021-1331 affects Cisco Small Business RV016, RV042, RV042G, RV082, RV320, and RV325 routers. An attacker with valid administrator credentials could abuse the web management interface to run code as root or restart the device, causing outage. The supplied sources do not show active exploitation.

Executive priority

Treat as high priority for small-office, branch, or edge networks using these routers. The need for admin credentials lowers likelihood, but root execution and device reload can affect network availability and control.

Technical view

Cisco describes improper validation of user input in the web-based management interface. Crafted HTTP requests from an authenticated remote administrator can trigger arbitrary code execution on the underlying operating system as root or a denial-of-service reload. CVSS 3.1 is 7.2 with high privileges required.

Likely exposure

Exposure is limited to organizations running the named Cisco Small Business RV routers with reachable web-based management interfaces. Risk rises where administrator credentials are shared, weak, compromised, or where management access is exposed beyond trusted administrative networks.

Exploitation context

The attacker needs valid administrator credentials. The bundle marks KEV as false, and no supplied source states active exploitation. The impact is still serious because successful exploitation can grant root-level execution or force device reloads.

Researcher notes

Focus validation on authenticated management-interface exposure and affected RV-series models. The provided data identifies CWE-121 and improper input validation but does not provide detailed vulnerable version ranges, exploit artifacts, or confirmed exploitation evidence.

Mitigation direction

  • Review Cisco advisory cisco-sa-rv-overflow-ghZP68yj for fixed releases or vendor-approved mitigations.
  • Upgrade affected router firmware according to Cisco guidance where applicable.
  • Restrict web management access to trusted administrative paths only.
  • Rotate and audit router administrator credentials if compromise is suspected.

Validation and detection

  • Inventory Cisco RV016, RV042, RV042G, RV082, RV320, and RV325 routers.
  • Confirm each device firmware status against Cisco advisory guidance.
  • Check whether web management is reachable from untrusted networks.
  • Review administrative account ownership and recent management-interface access logs.
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.

Open ATT&CK lookup
cve · low confidence lookup

CVE-2021-1331 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-2021-1331Attack 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.