CVE-2021-1350

Name: CVE-2021-1350
Creator: NVD / NIST
Published: 2021-01-20T20:15:17.457+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.3/10EPSS 1.28%

Last modified Jun 17, 2026

CVE-2021-1350 is a medium-severity vulnerability rated 5.3/10 on the CVSS scale. A vulnerability in the web UI of Cisco Umbrella could allow an unauthenticated, remote attacker to negatively affect the performance of this service. The vulnerability exists due to insufficient rate limiting controls in the web UI. EPSS estimates a 1.28% chance of exploitation in the next 30 days.

Description

A vulnerability in the web UI of Cisco Umbrella could allow an unauthenticated, remote attacker to negatively affect the performance of this service. The vulnerability exists due to insufficient rate limiting controls in the web UI. An attacker could exploit this vulnerability by sending crafted HTTPS packets at a high and sustained rate. A successful exploit could allow the attacker to negatively affect the performance of the web UI. Cisco has addressed this vulnerability.

Metrics

CVSS 3.1

5.3/10

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

EPSS Probability

1.28%

66.4th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-770

Affected Software

Vendor	Product	Versions
Cisco	Umbrella	All versions

References

Timeline

Published: Jan 20, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-1350?

How severe is CVE-2021-1350?

CVE-2021-1350 has a CVSS score of 5.3/10 (MEDIUM severity). The EPSS model estimates a 1.28% probability of exploitation in the next 30 days.

How do I fix CVE-2021-1350?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-1350?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST