How severe is CVE-2021-21488?

CVE-2021-21488 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-21488 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (67th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-21488?

CVE-2021-21488 primarily affects Sap Netweaver Knowledge Management. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-21488?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-21488 published?

CVE-2021-21488 was published on 2021-03-09 and last updated on 2026-06-17.

CVE-2021-21488

CVE-2021-21488 is a medium-severity vulnerability in Sap Netweaver Knowledge Management with a CVSS 3.x base score of 6.5. 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-502.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 4.0
EPSS exploit prediction: 1% (67th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-502
Affected product: Sap Netweaver Knowledge Management
Published: 2021-03-09
Last modified: 2026-06-17

Description

Knowledge Management versions 7.01, 7.02, 7.30, 7.31, 7.40, 7.50 allows a remote attacker with basic privileges to deserialize user-controlled data without verification, leading to insecure deserialization which triggers the attacker’s code, therefore impacting Availability.

Frequently asked questions

What is CVE-2021-21488?: Knowledge Management versions 7.01, 7.02, 7.30, 7.31, 7.40, 7.50 allows a remote attacker with basic privileges to deserialize user-controlled data without verification, leading to insecure deserialization which triggers the attacker’s code, therefore impacting Availability.
How severe is CVE-2021-21488?: CVE-2021-21488 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-21488 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (67th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-21488?: CVE-2021-21488 primarily affects Sap Netweaver Knowledge Management. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-21488?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-21488 published?: CVE-2021-21488 was published on 2021-03-09 and last updated on 2026-06-17.

References

Affected products (6)

cpe:2.3:a:sap:netweaver_knowledge_management:7.01:*:*:*:*:*:*:*
cpe:2.3:a:sap:netweaver_knowledge_management:7.02:*:*:*:*:*:*:*
cpe:2.3:a:sap:netweaver_knowledge_management:7.30:*:*:*:*:*:*:*
cpe:2.3:a:sap:netweaver_knowledge_management:7.31:*:*:*:*:*:*:*
cpe:2.3:a:sap:netweaver_knowledge_management:7.40:*:*:*:*:*:*:*
cpe:2.3:a:sap:netweaver_knowledge_management:7.50:*:*:*:*:*:*:*

More vulnerabilities in Sap Netweaver Knowledge Management

CVE-2020-6284 — Critical (CVSS 9.0): SAP NetWeaver (Knowledge Management), versions - 7.30, 7.31, 7.40, 7.50, allows the automatic execution of script…
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