SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2023-20178

A vulnerability in the client update process of Cisco AnyConnect Secure Mobility Client Software for Windows and Cisco Secure Client Software for Windows could allow a low-privileged, authenticated, local attacker to elevate privileges to those of SYSTEM.

HIGH 7.8EPSS 5.37%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (5.37%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

A vulnerability in the client update process of Cisco AnyConnect Secure Mobility Client Software for Windows and Cisco Secure Client Software for Windows could allow a low-privileged, authenticated, local attacker to elevate privileges to those of SYSTEM. The client update process is executed after a successful VPN connection is established. This vulnerability exists because improper permissions are assigned to a temporary directory that is created during the update process. An attacker could exploit this vulnerability by abusing a specific function of the Windows installer process. A successful exploit could allow the attacker to execute code with SYSTEM privileges.

CVSS 3.1
7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS
5.37% probability · 93th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-276
Affected
cisco/anyconnect secure mobility client · cisco/secure client
Source
psirt@cisco.com
EPSS trend
0%5%10%26 October 2026: 5.37%26 October 202626 October 2026

EPSS 5.4% since 26 October 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.