CVE-2021-1612: Cisco IOS XE SD-WAN Software Arbitrary File Overwrite Vulnerability

Severity: high (CVSS 7.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-09-23 · updated 2026-06-17
Weakness: CWE-61

Description

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.

Affected products

Cisco Sd-Wan: before 17.3.4 — fixed in 17.3.4

How to fix

Upgrade to a fixed version: Cisco Sd-Wan 17.3.4. Check the vendor advisory for mitigations.

References

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