cvedb.io
CVE-2021-34741
HIGH · CVSS 7.5
EPSS exploitation probability: 0%
Published 2021-11-04T16:15:08.660 · Last modified 2026-06-17T03:56:28.320

Summary

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

cisco — asyncos

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.