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CVE-2021-34727

Cisco IOS XE SD-WAN Software Buffer Overflow Vulnerability

Published: Sep 23, 2021Updated: Nov 21, 2024 Sources: CVE List NVD BDUCWE-120
NVD MITRE
9.8CVSSCRITICAL
EPSS Score
2.5%
Top 17.0%
CISA KEV
Not in KEV
Exploits
0 Known
Remediation
Patch Available

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.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:HI:HA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:HAvailability
High
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Weaknesses

CWE-120

Affected Products

Cisco IOS XE SD-WANCisco Systems Inc.Networking Infrastructure
ios xe sd-wanciscoNetworking Infrastructure
Cisco IOS XE SD-WAN SoftwareCiscoNetworking Infrastructure
cisco systems inc.commercialUSNetworking Infrastructureaka cisco systems, cisco
ciscocommercialUSNetworking Infrastructureaka cisco systems, cisco systems inc.

Attack Graph

Products CVE Techniques Tactics

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Exploitability

0 exploit sources identified

Exploit details including PoC links, Metasploit modules, and scanner templates are available after registration.

View exploit details
Official Patch Available

MITRE ATT&CK

2 techniques
Initial Access
Privilege Escalation
View detailed technique mapping

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxesdwan-rbuffover-vE2OB6tp?vsfCisco20Security20AdvisoryvscatSecurity20IntelligencevstypeRSSvspCisco20IOS20XE20SD-WAN20Software20Buffer20Overflow20Vulnerabilityvsk1
tools.cisco.com
https://nvd.nist.gov/vuln/detail/CVE-2021-34727
nvd.nist.gov
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxesdwan-rbuffover-vE2OB6tp
tools.cisco.com

Timeline

Published
Sep 23, 2021
Last Updated
Nov 21, 2024

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