CVE-2021-1258
CWE-264Published: January 13, 2021· Updated: Jun 17, 2026
Official Description
A vulnerability in the upgrade component of Cisco AnyConnect Secure Mobility Client could allow an authenticated, local attacker with low privileges to read arbitrary files on the underlying operating system (OS) of an affected device. The vulnerability is due to insufficient file permission restrictions. An attacker could exploit this vulnerability by sending a crafted command from the local CLI to the application. A successful exploit could allow the attacker to read arbitrary files on the underlying OS of the affected device. The attacker would need to have valid user credentials to exploit this vulnerability.
Technical Analysis
CVE-2021-1258 requires local access, meaning attackers must already have a foothold on the target system.
Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.
A successful exploit results in complete confidentiality breach (data exposure), with a CVSS base score of 5.5.
CVSS v3.1 Vector Breakdown
Affected Vendors & Products
Exploit & PoC Resources
Official Patches & Advisories
All References (4)
Quick Facts
Related CVEs (CWE-264)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2021-1258 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts