CVE-2021-47005
CVE-2021-47005 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-476.
Key facts
- Severity: Medium (CVSS 3.x base score 5.5)
- EPSS exploit prediction: 0% (14th percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2021-33653
- Weakness: CWE-476
- Affected product: Linux Linux Kernel
- Published:
- Last modified:
Description
In the Linux kernel, the following vulnerability has been resolved: PCI: endpoint: Fix NULL pointer dereference for ->get_features() get_features ops of pci_epc_ops may return NULL, causing NULL pointer dereference in pci_epf_test_alloc_space function. Let us add a check for pci_epc_feature pointer in pci_epf_test_bind before we access it to avoid any such NULL pointer dereference and return -ENOTSUPP in case pci_epc_feature is not found. When the patch is not applied and EPC features is not implemented in the platform driver, we see the following dump due to kernel NULL pointer dereference. Call trace: pci_epf_test_bind+0xf4/0x388 pci_epf_bind+0x3c/0x80 pci_epc_epf_link+0xa8/0xcc configfs_symlink+0x1a4/0x48c vfs_symlink+0x104/0x184 do_symlinkat+0x80/0xd4 __arm64_sys_symlinkat+0x1c/0x24 el0_svc_common.constprop.3+0xb8/0x170 el0_svc_handler+0x70/0x88 el0_svc+0x8/0x640 Code: d2800581 b9403ab9 f9404ebb 8b394f60 (f9400400) ---[ end trace a438e3c5a24f9df0 ]---
Frequently asked questions
- What is CVE-2021-47005?
- In the Linux kernel, the following vulnerability has been resolved: PCI: endpoint: Fix NULL pointer dereference for ->get_features() get_features ops of pci_epc_ops may return NULL, causing NULL pointer dereference in pci_epf_test_alloc_space function. Let us add a check for pci_epc_feature pointer in pci_epf_test_bind before we access it to avoid any such NULL pointer dereference and return -ENOTSUPP in case pci_epc_feature is not found. When the patch is not applied and EPC features is not implemented in the platform driver, we see the following dump due to kernel NULL pointer dereference. Call trace: pci_epf_test_bind+0xf4/0x388 pci_epf_bind+0x3c/0x80 pci_epc_epf_link+0xa8/0xcc configfs_symlink+0x1a4/0x48c vfs_symlink+0x104/0x184 do_symlinkat+0x80/0xd4 __arm64_sys_symlinkat+0x1c/0x24 el0_svc_common.constprop.3+0xb8/0x170 el0_svc_handler+0x70/0x88 el0_svc+0x8/0x640 Code: d2800581 b9403ab9 f9404ebb 8b394f60 (f9400400) ---[ end trace a438e3c5a24f9df0 ]---
- How severe is CVE-2021-47005?
- CVE-2021-47005 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-2021-47005 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (14th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-47005?
- CVE-2021-47005 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-47005?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- Does CVE-2021-47005 have an EU (EUVD) identifier?
- Yes. CVE-2021-47005 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-33653.
- When was CVE-2021-47005 published?
- CVE-2021-47005 was published on 2024-02-28 and last updated on 2026-06-17.
References
- https://git.kernel.org/stable/c/0169d4f0bee44fdfef908c13ed21fcb326c38695
- https://git.kernel.org/stable/c/6613bc2301ba291a1c5a90e1dc24cf3edf223c03
- https://git.kernel.org/stable/c/679ebad058b8168f10e63876d63b0877fd2fe784
- https://git.kernel.org/stable/c/bbed83d7060e07a5d309104d25a00f0a24441428
Affected products (1)
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
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