How severe is CVE-2020-4821?

CVE-2020-4821 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-4821 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-4821?

CVE-2020-4821 primarily affects Ibm Infosphere Data Replication. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-4821?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2020-4821 published?

CVE-2020-4821 was published on 2021-07-16 and last updated on 2026-06-17.

CVE-2020-4821

CVE-2020-4821 is a critical-severity vulnerability in Ibm Infosphere Data Replication with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-287.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 6.8
EPSS exploit prediction: 2% (78th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Ibm Infosphere Data Replication
Published: 2021-07-16
Last modified: 2026-06-17

Description

IBM InfoSphere Data Replication 11.4 and IBM InfoSphere Change Data Capture for z/OS 10.2.1, under certain configurations, could allow a user to bypass authentication mechanisms using an empty password string. IBM X-Force ID: 189834

Frequently asked questions

What is CVE-2020-4821?: IBM InfoSphere Data Replication 11.4 and IBM InfoSphere Change Data Capture for z/OS 10.2.1, under certain configurations, could allow a user to bypass authentication mechanisms using an empty password string. IBM X-Force ID: 189834
How severe is CVE-2020-4821?: CVE-2020-4821 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-4821 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-4821?: CVE-2020-4821 primarily affects Ibm Infosphere Data Replication. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-4821?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2020-4821 published?: CVE-2020-4821 was published on 2021-07-16 and last updated on 2026-06-17.

References

Affected products (5)

cpe:2.3:a:ibm:infosphere_data_replication:11.4:*:*:*:*:*:*:*
cpe:2.3:a:ibm:infosphere_data_replication:11.4.0:*:*:*:*:*:*:*
cpe:2.3:a:ibm:infosphere_change_data_capture:10.2.1:*:*:*:*:z\/os:*:*
cpe:2.3:a:ibm:infosphere_change_data_capture:11.3.3:*:*:*:*:z\/os:*:*
cpe:2.3:a:ibm:infosphere_change_data_capture:11.4:*:*:*:*:z\/os:*:*

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