CVE-2021-34727

Cisco IOS XE SD-WAN Software Buffer Overflow Vulnerability

Description

A vulnerability in the vDaemon process in Cisco IOS XE SD-WAN Software could allow an unauthenticated, remote attacker to cause a buffer overflow on an affected device. This vulnerability is due to insufficient bounds checking when an affected device processes traffic. An attacker could exploit this vulnerability by sending crafted traffic to the device. A successful exploit could allow the attacker to cause a buffer overflow and possibly execute arbitrary commands with root-level privileges, or cause the device to reload, which could result in a denial of service condition.

Category

9.8
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 1.00% Top 25%
Vendor Advisory cisco.com
Affected: Cisco Cisco IOS XE SD-WAN Software
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2021-34727?
CVE-2021-34727 has been scored as a critical severity vulnerability.
How to fix CVE-2021-34727?
To fix CVE-2021-34727, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-34727 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-34727 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-34727?
CVE-2021-34727 affects Cisco Cisco IOS XE SD-WAN Software.
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