7.5

CVE-2021-34741: cisco asyncos

CVSS: 7.5v3.1HighModified
Published 04-11-2021Last modified 07-11-2024

Vulnerability summary

CVE-2021-34741 is a high (CVSS 7.5) vulnerability in cisco asyncos. EPSS estimates a 1.29% chance of exploitation in the next 30 days, higher than 69.8% of scored vulnerabilities.

Overall risk
30/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.5/10
010
High · v3.1 (CVE.org)
EPSS score
1.29%
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. 04-11-2021
    PublishedVulnerability first disclosed.
  2. 07-11-2024
    Last modifiedVulnerability information updated.

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.

CVSS metrics

3 scores · 2 sources · 2 versions

EPSS trend

Probability

1.29%

Chance of exploitation in the next 30 days

Percentile

70%

Versus all other CVEs

30-day change

0.00 pp

From 1.29% on 20-09-2026

20-09-202620-10-2026
EPSS score
1.29%

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

Cisco2 products

1 vendor · 2 products

References

1 links