cvedb.io
CVE-2021-34793
HIGH · CVSS 8.6
EPSS exploitation probability: 0%
Published 2021-10-27T19:15:08.563 · Last modified 2026-06-17T03:56:35.060

Summary

A vulnerability in the TCP Normalizer of Cisco Adaptive Security Appliance (ASA) Software and Firepower Threat Defense (FTD) Software operating in transparent mode could allow an unauthenticated, remote attacker to poison MAC address tables, resulting in a denial of service (DoS) vulnerability. This vulnerability is due to incorrect handling of certain TCP segments when the affected device is operating in transparent mode. An attacker could exploit this vulnerability by sending a crafted TCP segment through an affected device. A successful exploit could allow the attacker to poison the MAC address tables in adjacent devices, resulting in network disruption.

Affected products

cisco — adaptive_security_appliance

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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.