SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

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…

CRITICAL 9.8EPSS 18.5%

Does this matter?

EPSS puts the probability of exploitation in the next 30 days at 18.5%, higher than 97% of all known CVEs. Patch or mitigate before the next change window.

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.

CVSS 3.1
9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
18.50% probability · 97th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-121, CWE-787
Affected
cisco/application extension platform · cisco/rv110w wireless-n vpn firewall firmware · cisco/rv130 vpn router firmware · cisco/rv130w wireless-n multifunction vpn router firmware · cisco/rv215w wireless-n vpn router firmware
Source
psirt@cisco.com
EPSS trend
0%10%20%3 November 2026: 18.50%3 November 20263 November 2026

EPSS 18.5% since 3 November 2026; no change recorded yet. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.