How severe is CVE-2021-47056?

CVE-2021-47056 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-2021-47056 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (13th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-47056?

CVE-2021-47056 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-47056?

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

Does CVE-2021-47056 have an EU (EUVD) identifier?

Yes. CVE-2021-47056 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-33704.

When was CVE-2021-47056 published?

CVE-2021-47056 was published on 2024-02-29 and last updated on 2026-06-17.

CVE-2021-47056

CVE-2021-47056 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-908.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
EPSS exploit prediction: 0% (13th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2021-33704
Weakness: CWE-908
Affected product: Linux Linux Kernel
Published: 2024-02-29
Last modified: 2026-06-17

Description

In the Linux kernel, the following vulnerability has been resolved: crypto: qat - ADF_STATUS_PF_RUNNING should be set after adf_dev_init ADF_STATUS_PF_RUNNING is (only) used and checked by adf_vf2pf_shutdown() before calling adf_iov_putmsg()->mutex_lock(vf2pf_lock), however the vf2pf_lock is initialized in adf_dev_init(), which can fail and when it fail, the vf2pf_lock is either not initialized or destroyed, a subsequent use of vf2pf_lock will cause issue. To fix this issue, only set this flag if adf_dev_init() returns 0. [ 7.178404] BUG: KASAN: user-memory-access in __mutex_lock.isra.0+0x1ac/0x7c0 [ 7.180345] Call Trace: [ 7.182576] mutex_lock+0xc9/0xd0 [ 7.183257] adf_iov_putmsg+0x118/0x1a0 [intel_qat] [ 7.183541] adf_vf2pf_shutdown+0x4d/0x7b [intel_qat] [ 7.183834] adf_dev_shutdown+0x172/0x2b0 [intel_qat] [ 7.184127] adf_probe+0x5e9/0x600 [qat_dh895xccvf]

Frequently asked questions

What is CVE-2021-47056?: In the Linux kernel, the following vulnerability has been resolved: crypto: qat - ADF_STATUS_PF_RUNNING should be set after adf_dev_init ADF_STATUS_PF_RUNNING is (only) used and checked by adf_vf2pf_shutdown() before calling adf_iov_putmsg()->mutex_lock(vf2pf_lock), however the vf2pf_lock is initialized in adf_dev_init(), which can fail and when it fail, the vf2pf_lock is either not initialized or destroyed, a subsequent use of vf2pf_lock will cause issue. To fix this issue, only set this flag if adf_dev_init() returns 0. [ 7.178404] BUG: KASAN: user-memory-access in __mutex_lock.isra.0+0x1ac/0x7c0 [ 7.180345] Call Trace: [ 7.182576] mutex_lock+0xc9/0xd0 [ 7.183257] adf_iov_putmsg+0x118/0x1a0 [intel_qat] [ 7.183541] adf_vf2pf_shutdown+0x4d/0x7b [intel_qat] [ 7.183834] adf_dev_shutdown+0x172/0x2b0 [intel_qat] [ 7.184127] adf_probe+0x5e9/0x600 [qat_dh895xccvf]
How severe is CVE-2021-47056?: CVE-2021-47056 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-2021-47056 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (13th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-47056?: CVE-2021-47056 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-47056?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2021-47056 have an EU (EUVD) identifier?: Yes. CVE-2021-47056 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-33704.
When was CVE-2021-47056 published?: CVE-2021-47056 was published on 2024-02-29 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

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