CVE-2021-20501

mediumpriority · track · 33EPSS 0.013 · 71 %ileEUUS
grimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
1.34% (71st) EPSS
CVSS 6.4 · medium
Is it mine?
8 products
Check your exposure
Who says so?
3 sources
cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-27

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.

01

cvss

Technical severity, 0–10. One row per scoring source.

8.2
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5.9–8.2

v2.06.4mediumAV:N/AC:L/Au:N/C:N/I:P/A:Pprimary · NVD / NIST USexploitability 10 · impact 4.9
v3.18.2highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 4.2
v3.05.9mediumCVSS:3.0/AV:N/C:N/S:U/AC:H/A:H/UI:N/I:N/PR:N/RC:C/E:U/RL:Osecondary · ENISA EU
v3.05.9mediumCVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · psirt@us.ibm.com USexploitability 2.2 · impact 3.6
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H/E:Usecondary · CVSS-BT (t0sche)
02

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-400USLLM-inferredCWE-425USLLM-inferred
03

affected products (8)

Products and version ranges known to be affected.

04

also known as (3)

Other names and identifiers for this entity.

05

sources

Which sources assert this record, and when.

cnnvdenisa_euvdnvdNVDCVE.orgMITRE
published 2021-04-21modified 2026-06-17
06

references (9)

External citations — patches, advisories, analysis.

scry

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