CVE-2021-20501: High severity ibm iseries as/400 vulnerability

Published Apr 20, 2021
·
Updated

IBM i 7.1, 7.2, 7.3, and 7.4 SMTP allows a network attacker to send emails to non-existent local-domain recipients to the SMTP server, caused by using a non-default configuration. An attacker could exploit this vulnerability to consume unnecessary network bandwidth and disk space, and allow remote attackers to send spam email. IBM X-Force ID: 198056.

Other sources

IBM i SMTP allows a network attacker to send emails to non-existent local-domain recipients to the SMTP server, caused by using a non-default configuration. An attacker could exploit this vulnerability to consume unnecessary network bandwidth and disk space, and allow remote attackers to send spam email.

IBM

Affected Software

8 affected components
IBM i<=7.4
IBM i<=7.3
IBM i<=7.2
IBM i<=7.1
IBM i=7.1
IBM i=7.2
IBM i=7.3
IBM i=7.4

Event History

Apr 20, 2021
CVE Published
via IBM·12:00 AM
Apr 21, 2021
CVE Published
via MITRE·12:05 PM
Data Sourced
via MITRE·12:05 PM
DescriptionSeverityWeakness

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is the severity of CVE-2021-20501?

CVE-2021-20501 has a medium severity rating due to the potential for network resource consumption.

2

How do I fix CVE-2021-20501?

To mitigate CVE-2021-20501, review and adjust the SMTP server configuration to prevent emails to non-existent local-domain recipients.

3

What versions of IBM i are affected by CVE-2021-20501?

CVE-2021-20501 affects IBM i versions 7.1, 7.2, 7.3, and 7.4.

4

What impact does CVE-2021-20501 have on network resources?

CVE-2021-20501 can lead to excessive consumption of network bandwidth and disk space.

5

Can CVE-2021-20501 be exploited remotely?

Yes, CVE-2021-20501 can be exploited by remote attackers through the SMTP server.

Contact

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