High severity · published Apr 21, 2021
CVE-2021-20501
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
8.2
CVSS
1.3%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
Low
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.3% · higher than 71% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
I
I · Ibm
7.1; 7.2; 7.3; 7.4 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-20501
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-20501
VDB Entry
https://exchange.xforce.ibmcloud.com/vulnerabilities/198056
Vendor Advisory
https://www.ibm.com/support/pages/node/6445505
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