8.6

CVE-2021-34793: cisco adaptive_security_appliance

CVSS: 8.6v3.1HighModified
Published 27-10-2021Last modified 07-11-2024
Open JSON

Vulnerability summary

CVE-2021-34793 is a high (CVSS 8.6) vulnerability in cisco adaptive_security_appliance. EPSS estimates a 0.59% chance of exploitation in the next 30 days, higher than 46.9% of scored vulnerabilities.

Overall risk
35/100
0100
Medium · default modelHow is this calculated?
CVSS score
8.6/10
010
High · v3.1 (CVE.org)
EPSS score
0.59%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 27-10-2021
    PublishedVulnerability first disclosed.
  2. 07-11-2024
    Last modifiedVulnerability information updated.

Description

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.

CVSS metrics

3 scores · 2 sources · 2 versions

EPSS trend

Probability

0.59%

Chance of exploitation in the next 30 days

Percentile

47%

Versus all other CVEs

30-day change

0.00 pp

From 0.58% on 18-09-2026

18-09-202618-10-2026
EPSS score
0.59%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Cisco12 products

1 vendor · 12 products

References

1 links