What is CVE-2021-1612?

CVE-2021-1612 is a medium-severity vulnerability in Cisco iOS Xe Sd-Wan Software, classified under UNIX Symbolic Link (Symlink) Following. CVSS score: 5.5/10. Published 2021-09-23.

How severe is CVE-2021-1612?

Medium severity. CVSS v3 base score is 5.5 out of 10.

Vulnerability in Cisco iOS Xe Sd-Wan Software

CVE-2021-1612

A vulnerability in the Cisco IOS XE SD-WAN Software CLI could allow an authenticated, local attacker to overwrite arbitrary files on the local system. This vulnerability is due to improper access controls on files within the local file system. An attacker could exploit this vulnerability by placing a symbolic link in a specific location on the local file system. A successful exploit could allow the attacker to overwrite arbitrary files on an affected device.

Published 2021-09-23 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N.

EPSS exploit prediction

EPSS: 0.003 (15.4th percentile), scored 2026-10-24.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 15th percentile — 15.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000

Affected products

Weakness classification (CWE)

References

tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sd-wan-G… (vendor-advisory, Patch, Vendor Advisory)

Frequently asked questions

What is CVE-2021-1612?: CVE-2021-1612 is a medium-severity vulnerability in Cisco iOS Xe Sd-Wan Software, classified under UNIX Symbolic Link (Symlink) Following. CVSS score: 5.5/10. Published 2021-09-23.
How severe is CVE-2021-1612?: Medium severity. CVSS v3 base score is 5.5 out of 10.