CVE-2021-1461: Signature Bypass (CVSS 4.9)

Description

A vulnerability in the Image Signature Verification feature of Cisco SD-WAN Software could allow an authenticated, remote attacker with Administrator-level credentials to install a malicious software patch on an affected device. The vulnerability is due to improper verification of digital signatures for patch images. An attacker could exploit this vulnerability by crafting an unsigned software patch to bypass signature checks and loading it on an affected device. A successful exploit could allow the attacker to boot a malicious software patch image.Cisco has released software updates that address the vulnerability described in this advisory. There are no workarounds that address this vulnerability.

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CVSS v3.1 Score

4.9

MEDIUM

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

Weakness Type (CWE)

CWE-347 CWE-347

References

Other References

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-xss-webui-gQLSFyPM https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sdwan-sigverbypass-gPYXd6Mk

Frequently Asked Questions

What is CVE-2021-1461? +

A vulnerability in the Image Signature Verification feature of Cisco SD-WAN Software could allow an authenticated, remote attacker with Administrator-level credentials to install a malicious software patch on an affected device. The vulnerability is due to improper verification of digital signatures for patch images. An attacker could exploit this vulnerability by crafting an unsigned software patch to bypass signature checks and loading it on an affected device. A successful exploit could allow the attacker to boot a malicious software patch image.Cisco has released software updates that address the vulnerability described in this advisory. There are no workarounds that address this vulnerability. It has a CVSS v3.1 base score of 4.9 (MEDIUM).

How severe is CVE-2021-1461? +

CVE-2021-1461 has a CVSS v3.1 score of 4.9 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

How do I check if I'm vulnerable to CVE-2021-1461? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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CVE-2021-1461