How severe is CVE-2021-20491?

CVE-2021-20491 has a CVSS 3.x base score of 4.4, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-20491 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (17th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-20491?

CVE-2021-20491 primarily affects Ibm Spectrum Protect. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-20491?

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

When was CVE-2021-20491 published?

CVE-2021-20491 was published on 2021-04-16 and last updated on 2026-06-17.

CVE-2021-20491

CVE-2021-20491 is a medium-severity vulnerability in Ibm Spectrum Protect with a CVSS 3.x base score of 4.4. 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-787.

Key facts

Severity: Medium (CVSS 3.x base score 4.4)
CVSS v2: 2.1
EPSS exploit prediction: 0% (17th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Ibm Spectrum Protect
Published: 2021-04-16
Last modified: 2026-06-17

Description

IBM Spectrum Protect Server 7.1 and 8.1 is subject to a stack-based buffer overflow caused by improper bounds checking during the parsing of commands. By issuing such a command with an improper parameter, an authorized administrator could overflow a buffer and cause the server to crash. IBM X-Force ID: 197792.

Frequently asked questions

What is CVE-2021-20491?: IBM Spectrum Protect Server 7.1 and 8.1 is subject to a stack-based buffer overflow caused by improper bounds checking during the parsing of commands. By issuing such a command with an improper parameter, an authorized administrator could overflow a buffer and cause the server to crash. IBM X-Force ID: 197792.
How severe is CVE-2021-20491?: CVE-2021-20491 has a CVSS 3.x base score of 4.4, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-20491 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (17th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-20491?: CVE-2021-20491 primarily affects Ibm Spectrum Protect. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-20491?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-20491 published?: CVE-2021-20491 was published on 2021-04-16 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:ibm:spectrum_protect:*:*:*:*:*:*:*:*
cpe:2.3:a:ibm:spectrum_protect:8.1.11.000:*:*:*:*:*:*:*

More vulnerabilities in Ibm Spectrum Protect

CVE-2020-4415 — Critical (CVSS 9.8): IBM Spectrum Protect 7.1 and 8.1 server is vulnerable to a stack-based buffer overflow, caused by improper bounds…
CVE-2020-4222 — Critical (CVSS 9.8): IBM Spectrum Protect Plus 10.1.0 and 10.1.5 could allow a remote attacker to execute arbitrary code on the system. By…
CVE-2020-4213 — Critical (CVSS 9.8): IBM Spectrum Protect Plus 10.1.0 and 10.1.5 could allow a remote attacker to execute arbitrary code on the system. By…
CVE-2020-4212 — Critical (CVSS 9.8): IBM Spectrum Protect Plus 10.1.0 and 10.1.5 could allow a remote attacker to execute arbitrary code on the system. By…
CVE-2020-4211 — Critical (CVSS 9.8): IBM Spectrum Protect Plus 10.1.0 and 10.1.5 could allow a remote attacker to execute arbitrary code on the system. By…
CVE-2020-4210 — Critical (CVSS 9.8): IBM Spectrum Protect Plus 10.1.0 and 10.1.5 could allow a remote attacker to execute arbitrary code on the system. By…

All CVEs affecting Ibm Spectrum Protect →

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