How severe is CVE-2020-25656?

CVE-2020-25656 has a CVSS 3.x base score of 4.1, rated medium severity. It is exploitable over local access with high attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2020-25656 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (35th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-25656?

CVE-2020-25656 primarily affects Redhat Enterprise Linux. In total, 11 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-25656?

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

When was CVE-2020-25656 published?

CVE-2020-25656 was published on 2020-12-02 and last updated on 2026-06-17.

CVE-2020-25656

CVE-2020-25656 is a medium-severity vulnerability in Redhat Enterprise Linux with a CVSS 3.x base score of 4.1. 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-416.

Key facts

Severity: Medium (CVSS 3.x base score 4.1)
CVSS v2: 1.9
EPSS exploit prediction: 0% (35th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-416
Affected product: Redhat Enterprise Linux
Published: 2020-12-02
Last modified: 2026-06-17

Description

A flaw was found in the Linux kernel. A use-after-free was found in the way the console subsystem was using ioctls KDGKBSENT and KDSKBSENT. A local user could use this flaw to get read memory access out of bounds. The highest threat from this vulnerability is to data confidentiality.

Frequently asked questions

What is CVE-2020-25656?: A flaw was found in the Linux kernel. A use-after-free was found in the way the console subsystem was using ioctls KDGKBSENT and KDSKBSENT. A local user could use this flaw to get read memory access out of bounds. The highest threat from this vulnerability is to data confidentiality.
How severe is CVE-2020-25656?: CVE-2020-25656 has a CVSS 3.x base score of 4.1, rated medium severity. It is exploitable over local access with high attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2020-25656 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (35th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-25656?: CVE-2020-25656 primarily affects Redhat Enterprise Linux. In total, 11 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-25656?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-25656 published?: CVE-2020-25656 was published on 2020-12-02 and last updated on 2026-06-17.

References

Affected products (11)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.10:rc1:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
cpe:2.3:a:starwindsoftware:starwind_virtual_san:v8:build12533:*:*:*:vsphere:*:*
cpe:2.3:a:starwindsoftware:starwind_virtual_san:v8:build12658:*:*:*:vsphere:*:*
cpe:2.3:a:starwindsoftware:starwind_virtual_san:v8:build12859:*:*:*:vsphere:*:*
cpe:2.3:a:starwindsoftware:starwind_virtual_san:v8:build13170:*:*:*:vsphere:*:*
cpe:2.3:a:starwindsoftware:starwind_virtual_san:v8:build13586:*:*:*:vsphere:*:*
cpe:2.3:a:starwindsoftware:starwind_virtual_san:v8:build13861:*:*:*:vsphere:*:*

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