CVE-2021-34730
CVE-2021-34730 is a critical-severity vulnerability in Cisco Application Extension Platform with a CVSS 3.x base score of 9.8. Its EPSS exploit-prediction score of 14% places it in the 96th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-787.
Key facts
- Severity: Critical (CVSS 3.x base score 9.8)
- CVSS v2: 10.0
- EPSS exploit prediction: 14% (96th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-787
- Affected product: Cisco Application Extension Platform
- Published:
- Last modified:
Description
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.
Frequently asked questions
- What is 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.
- How severe is CVE-2021-34730?
- CVE-2021-34730 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2021-34730 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 14% (96th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-34730?
- CVE-2021-34730 primarily affects Cisco Application Extension Platform. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2021-34730?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
- When was CVE-2021-34730 published?
- CVE-2021-34730 was published on 2021-08-18 and last updated on 2026-06-17.
References
Affected products (5)
- 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:rv130_vpn_router_firmware:-:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:rv130w_wireless-n_multifunction_vpn_router_firmware:-:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:rv215w_wireless-n_vpn_router_firmware:-:*:*:*:*:*:*:*
More vulnerabilities in Cisco Application Extension Platform
- CVE-2021-1216 — High (CVSS 7.2): Multiple vulnerabilities in the web-based management interface of Cisco Small Business RV110W, RV130, RV130W, and…
- CVE-2021-1215 — High (CVSS 7.2): Multiple vulnerabilities in the web-based management interface of Cisco Small Business RV110W, RV130, RV130W, and…
- CVE-2021-1214 — High (CVSS 7.2): Multiple vulnerabilities in the web-based management interface of Cisco Small Business RV110W, RV130, RV130W, and…
- CVE-2021-1213 — High (CVSS 7.2): Multiple vulnerabilities in the web-based management interface of Cisco Small Business RV110W, RV130, RV130W, and…
- CVE-2021-1212 — High (CVSS 7.2): Multiple vulnerabilities in the web-based management interface of Cisco Small Business RV110W, RV130, RV130W, and…
- CVE-2021-1211 — High (CVSS 7.2): Multiple vulnerabilities in the web-based management interface of Cisco Small Business RV110W, RV130, RV130W, and…
All CVEs affecting Cisco Application Extension Platform →
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