CVE-2021-34730 Vulnerability Analysis & Exploit Details

CVE-2021-34730
Vulnerability Scoring

9.8
/10
Critical Risk

As a catastrophic security flaw, CVE-2021-34730 has severe implications, demanding immediate intervention.

Attack Complexity Details

  • Attack Complexity: Low
    Exploits can be performed without significant complexity or special conditions.
  • Attack Vector: Network
    Vulnerability is exploitable over a network without physical access.
  • Privileges Required: None
    No privileges are required for exploitation.
  • Scope: Unchanged
    Exploit remains within the originally vulnerable component.
  • User Interaction: None
    No user interaction is necessary for exploitation.

CVE-2021-34730 Details

Status: Modified

Last updated: 🕕 21 Nov 2024, 06:11 UTC
Originally published on: 🕗 18 Aug 2021, 20:15 UTC

Time between publication and last update: 1190 days

CVSS Release: version 3

CVSS3 Source

ykramarz@cisco.com

CVSS3 Type

Secondary

CVSS3 Vector

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

CVE-2021-34730 Vulnerability Summary

CVE-2021-34730: A vulnerability in the Universal Plug-and-Play (UPnP) service of Cisco Small Business RV110W, RV130, RV130W, and RV215W Routers could allow an unauthenticated, remote attacker to execute arbitrary code or cause an affected device to restart unexpectedly, resulting in a denial of service (DoS) condition. This vulnerability is due to improper validation of incoming UPnP traffic. An attacker could exploit this vulnerability by sending a crafted UPnP request 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 DoS condition. Cisco has not released software updates that address this vulnerability.

Assessing the Risk of CVE-2021-34730

Access Complexity Graph

The exploitability of CVE-2021-34730 depends on two key factors: attack complexity (the level of effort required to execute an exploit) and privileges required (the access level an attacker needs).

Exploitability Analysis for CVE-2021-34730

With low attack complexity and no required privileges, CVE-2021-34730 is an easy target for cybercriminals. Organizations should prioritize immediate mitigation measures to prevent unauthorized access and data breaches.

Understanding AC and PR

A lower complexity and fewer privilege requirements make exploitation easier. Security teams should evaluate these aspects to determine the urgency of mitigation strategies, such as patch management and access control policies.

Attack Complexity (AC) measures the difficulty in executing an exploit. A high AC means that specific conditions must be met, making an attack more challenging, while a low AC means the vulnerability can be exploited with minimal effort.

Privileges Required (PR) determine the level of system access necessary for an attack. Vulnerabilities requiring no privileges are more accessible to attackers, whereas high privilege requirements limit exploitation to authorized users with elevated access.

CVSS Score Breakdown Chart

Above is the CVSS Sub-score Breakdown for CVE-2021-34730, illustrating how Base, Impact, and Exploitability factors combine to form the overall severity rating. A higher sub-score typically indicates a more severe or easier-to-exploit vulnerability.

CIA Impact Analysis

Below is the Impact Analysis for CVE-2021-34730, showing how Confidentiality, Integrity, and Availability might be affected if the vulnerability is exploited. Higher values usually signal greater potential damage.

  • Confidentiality: High
    Exploiting CVE-2021-34730 can result in unauthorized access to sensitive data, severely compromising data privacy.
  • Integrity: High
    CVE-2021-34730 could allow unauthorized modifications to data, potentially affecting system reliability and trust.
  • Availability: High
    CVE-2021-34730 can disrupt system operations, potentially causing complete denial of service (DoS).

Exploit Prediction Scoring System (EPSS)

The EPSS score estimates the probability that this vulnerability will be exploited in the near future.

EPSS Score: 0.567% (probability of exploit)

EPSS Percentile: 78.12% (lower percentile = lower relative risk)
This vulnerability is less risky than approximately 21.879999999999995% of others.

CVE-2021-34730 References

External References

CWE Common Weakness Enumeration

CWE-787

Vulnerable Configurations

  • cpe:2.3:a:cisco:application_extension_platform:1.0.3.55:*:*:*:*:*:*:*
    cpe:2.3:a:cisco:application_extension_platform:1.0.3.55:*:*:*:*:*:*:*
  • cpe:2.3:o:cisco:rv110w_wireless-n_vpn_firewall_firmware:-:*:*:*:*:*:*:*
    cpe:2.3:o:cisco:rv110w_wireless-n_vpn_firewall_firmware:-:*:*:*:*:*:*:*
  • cpe:2.3:h:cisco:rv110w_wireless-n_vpn_firewall:-:*:*:*:*:*:*:*
    cpe:2.3:h:cisco:rv110w_wireless-n_vpn_firewall:-:*:*:*:*:*:*:*
  • cpe:2.3:o:cisco:rv130_vpn_router_firmware:-:*:*:*:*:*:*:*
    cpe:2.3:o:cisco:rv130_vpn_router_firmware:-:*:*:*:*:*:*:*
  • cpe:2.3:h:cisco:rv130_vpn_router:-:*:*:*:*:*:*:*
    cpe:2.3:h:cisco:rv130_vpn_router:-:*:*:*:*:*:*:*
  • cpe:2.3:o:cisco:rv130w_wireless-n_multifunction_vpn_router_firmware:-:*:*:*:*:*:*:*
    cpe:2.3:o:cisco:rv130w_wireless-n_multifunction_vpn_router_firmware:-:*:*:*:*:*:*:*
  • cpe:2.3:h:cisco:rv130w_wireless-n_multifunction_vpn_router:-:*:*:*:*:*:*:*
    cpe:2.3:h:cisco:rv130w_wireless-n_multifunction_vpn_router:-:*:*:*:*:*:*:*
  • cpe:2.3:o:cisco:rv215w_wireless-n_vpn_router_firmware:-:*:*:*:*:*:*:*
    cpe:2.3:o:cisco:rv215w_wireless-n_vpn_router_firmware:-:*:*:*:*:*:*:*
  • cpe:2.3:h:cisco:rv215w_wireless-n_vpn_router:-:*:*:*:*:*:*:*
    cpe:2.3:h:cisco:rv215w_wireless-n_vpn_router:-:*:*:*:*:*:*:*

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