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CVE-2021-34741

Cisco Email Security Appliance Denial of Service Vulnerability

Published: Nov 4, 2021Updated: Nov 21, 2024 Sources: CVE List NVD BDUCWE-770
7.5HIGH
NVD MITRE
EPSS Score
1.2%
Top 33.5%
CISA KEV
Not in KEV
Exploits
0 Known
Remediation
Patch Available
Self-Check
OpenVAS

Description

A vulnerability in the email scanning algorithm of Cisco AsyncOS software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to perform a denial of service (DoS) attack against an affected device. This vulnerability is due to insufficient input validation of incoming emails. An attacker could exploit this vulnerability by sending a crafted email through Cisco ESA. A successful exploit could allow the attacker to exhaust all the available CPU resources on an affected device for an extended period of time, preventing other emails from being processed and resulting in a DoS condition.

No summary for this CVE yet.

CVSS Vector Breakdown

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

CWE-770

Affected Products

Cisco Systems Inc.
commercial·USaka cisco, cisco systems
AsyncOS
Networking Infrastructure
Cisco Email Security Appliance (ESA)
Networking Infrastructure
and 1 more affected products View all →

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
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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique
Impact
View detailed technique mapping

References

https://nvd.nist.gov/vuln/detail/CVE-2021-34741
nvd.nist.gov
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-esa-dos-JOm9ETfO
tools.cisco.com

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