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Vulnerability record · CVE-2021-1359 · published 8 July 2021

CVE-2021-1359: Cisco web security appliance vulnerability

Cisco · Web Security Appliance

A vulnerability in the configuration management of Cisco AsyncOS for Cisco Web Security Appliance (WSA) could allow an authenticated, remote attacker to perform command injection and elevate privileges to root. This vulnerability is due to insufficient validation of user-supplied XML input for the web interface. An attacker could exploit this vulnerability by uploading crafted XML configuration files that contain scripting code to a vulnerable device. A successful exploit could allow the attacker to execute arbitrary commands on the underlying operating system and elevate privileges to root. An attacker would need a valid user account with the rights to upload configuration files to exploit this vulnerability.

8.8 CVSS 3.1 High EPSS 1.9% · top 21.4% CWE-112 · CWE-112
8.8CVSS 3.1 base score, v2 9.0
1.9%EPSS exploitation probability, 30 days
NoNot in CISA KEV
2Affected product versions listed by NVD
2References
17 Jun 2026Last modified by NVD

Description

A vulnerability in the configuration management of Cisco AsyncOS for Cisco Web Security Appliance (WSA) could allow an authenticated, remote attacker to perform command injection and elevate privileges to root. This vulnerability is due to insufficient validation of user-supplied XML input for the web interface. An attacker could exploit this vulnerability by uploading crafted XML configuration files that contain scripting code to a vulnerable device. A successful exploit could allow the attacker to execute arbitrary commands on the underlying operating system and elevate privileges to root. An attacker would need a valid user account with the rights to upload configuration files to exploit this vulnerability.

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected products

2 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-scr-web-priv-esc-k3HCGJZ Vendor Advisory
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-scr-web-priv-esc-k3HCGJZ Vendor Advisory

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2021-1359), CISA KEV, FIRST EPSS (scores of 2026-09-28). This page is refreshed as NVD updates the record.