How severe is CVE-2021-47403?

CVE-2021-47403 has a CVSS 3.x base score of 7.1, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability high.

Is CVE-2021-47403 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (16th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-47403?

CVE-2021-47403 primarily affects Linux Linux Kernel. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-47403?

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

Does CVE-2021-47403 have an EU (EUVD) identifier?

Yes. CVE-2021-47403 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-34408.

When was CVE-2021-47403 published?

CVE-2021-47403 was published on 2024-05-21 and last updated on 2026-06-17.

CVE-2021-47403

CVE-2021-47403 is a high-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 7.1. 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-200.

Key facts

Severity: High (CVSS 3.x base score 7.1)
EPSS exploit prediction: 0% (16th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2021-34408
Weakness: CWE-200
Affected product: Linux Linux Kernel
Published: 2024-05-21
Last modified: 2026-06-17

Description

In the Linux kernel, the following vulnerability has been resolved: ipack: ipoctal: fix module reference leak A reference to the carrier module was taken on every open but was only released once when the final reference to the tty struct was dropped. Fix this by taking the module reference and initialising the tty driver data when installing the tty.

Frequently asked questions

What is CVE-2021-47403?: In the Linux kernel, the following vulnerability has been resolved: ipack: ipoctal: fix module reference leak A reference to the carrier module was taken on every open but was only released once when the final reference to the tty struct was dropped. Fix this by taking the module reference and initialising the tty driver data when installing the tty.
How severe is CVE-2021-47403?: CVE-2021-47403 has a CVSS 3.x base score of 7.1, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability high.
Is CVE-2021-47403 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (16th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-47403?: CVE-2021-47403 primarily affects Linux Linux Kernel. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-47403?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2021-47403 have an EU (EUVD) identifier?: Yes. CVE-2021-47403 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-34408.
When was CVE-2021-47403 published?: CVE-2021-47403 was published on 2024-05-21 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.15:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.15:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.15:rc3:*:*:*:*:*:*

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