CVE-2021-47494

CVE-2021-47494 is a medium-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 5.5. 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-667.

Key facts

Description

In the Linux kernel, the following vulnerability has been resolved: cfg80211: fix management registrations locking The management registrations locking was broken, the list was locked for each wdev, but cfg80211_mgmt_registrations_update() iterated it without holding all the correct spinlocks, causing list corruption. Rather than trying to fix it with fine-grained locking, just move the lock to the wiphy/rdev (still need the list on each wdev), we already need to hold the wdev lock to change it, so there's no contention on the lock in any case. This trivially fixes the bug since we hold one wdev's lock already, and now will hold the lock that protects all lists.

Frequently asked questions

What is CVE-2021-47494?
In the Linux kernel, the following vulnerability has been resolved: cfg80211: fix management registrations locking The management registrations locking was broken, the list was locked for each wdev, but cfg80211_mgmt_registrations_update() iterated it without holding all the correct spinlocks, causing list corruption. Rather than trying to fix it with fine-grained locking, just move the lock to the wiphy/rdev (still need the list on each wdev), we already need to hold the wdev lock to change it, so there's no contention on the lock in any case. This trivially fixes the bug since we hold one wdev's lock already, and now will hold the lock that protects all lists.
How severe is CVE-2021-47494?
CVE-2021-47494 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-47494 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (6th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-47494?
CVE-2021-47494 primarily affects Linux Linux Kernel. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-47494?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2021-47494 have an EU (EUVD) identifier?
Yes. CVE-2021-47494 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-34498.
When was CVE-2021-47494 published?
CVE-2021-47494 was published on 2024-05-22 and last updated on 2026-06-17.

References

Affected products (8)

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