Asyncos
CVE-2021-34741
HIGH
Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Lifecycle Timeline
1DescriptionNVD
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.
AnalysisAI
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). Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Technical ContextAI
This vulnerability is classified as Allocation of Resources Without Limits (CWE-770), which allows attackers to exhaust system resources through uncontrolled allocation. 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. Affected products include: Cisco Asyncos.
RemediationAI
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Set resource limits, implement rate limiting, validate input sizes.
A vulnerability in the web-based management interface of Cisco Email Security Appliance, Cisco Secure Email and Web Mana
A vulnerability in the configuration management of Cisco AsyncOS for Cisco Web Security Appliance (WSA) could allow an a
A vulnerability in the web management interface of Cisco AsyncOS Software for Cisco Web Security Appliance (WSA) could a
A vulnerability in the HTTPS decryption feature of Cisco Web Security Appliance (WSA) could allow an unauthenticated, re
A vulnerability in the web-based management interface of Cisco AsyncOS Software for Cisco Secure Email and Web Manager c
A vulnerability in the CLI of Cisco AsyncOS for Secure Web Appliance could allow an authenticated, local attacker to exe
A vulnerability in the log subscription subsystem of Cisco AsyncOS for the Cisco Secure Web Appliance (formerly Web Secu
A vulnerability in the administrative shell of Cisco AsyncOS on Cisco Email Security Appliance (ESA) and Content Securit
Cisco AsyncOS on Email Security Appliance (ESA) devices through 9.7.0-125 allows remote attackers to bypass malware dete
Cisco AsyncOS 9.7.0-125 on Email Security Appliance (ESA) devices allows remote attackers to bypass intended spam filter
A vulnerability in the DNS-based Authentication of Named Entities (DANE) email verification component of Cisco AsyncOS S
A vulnerability in the proxy service of Cisco AsyncOS for Cisco Web Security Appliance (WSA) could allow an unauthentica
Same technique Denial Of Service
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External POC / Exploit Code
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