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...
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
5.9
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.
- Record
CVE-2021-20501- CVSS 3.0
- 5.9 Medium
CVSS:3.0/AV:N/C:N/S:U/AC:H/A:H/UI:N/I:N/PR:N/RC:C/E:U/RL:O - Updated
- 2026-11-02
EUVDEUVD-2021-7919
5.9
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.
- Record
EUVD-2021-7919- CVSS 3.0
- 5.9 Medium
CVSS:3.0/AV:N/C:N/S:U/AC:H/A:H/UI:N/I:N/PR:N/RC:C/E:U/RL:O - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-5c9g-84hr-f4w2
8.2
IBM i 7.1, 7.2, 7.3, and 7.4 SMTP allows a network attacker to send emails to non-existent local...
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.
- Record
GHSA-5c9g-84hr-f4w2- CVSS 3.1
- 8.2 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H - Weakness
- CWE-400
- Updated
- 2026-11-02
NVD
8.2
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.
- Record
CVE-2021-20501- CVSS 3.1
- 8.2 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H - CVSS 3.0
- 5.9 Medium
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H - CVSS 2.0
- 6.4 Medium
AV:N/AC:L/Au:N/C:N/I:P/A:P - Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases, published | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-20501 is a medium vulnerability (CVSS 5.9) in Ibm I, published April 21, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.34%, the 71st percentile. No source names a fixed version.