Read the docs
TI-2021-22118 Aliases CVE-2021-47463GHSA-xjr2-g37g-hrjm

mm/secretmem: fix NULL page->mapping dereference in page_is_secretmem()

Priority LOW 24CWE-476Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 2 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-476.

Summary

In the Linux kernel, the following vulnerability has been resolved: mm/secretmem: fix NULL page->mapping dereference in page_is_secretmem() Check for a NULL page->mapping before dereferencing the mapping in page_is_secretmem(), as the page's mapping can be nullified while gup() is running, e.g. by reclaim or truncation. BUG: kernel NULL pointer dereference, address: 0000000000000068 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP NOPTI CPU: 6 PID: 4173897 Comm: CPU 3/KVM Tainted: G W RIP: 0010:internal_get_user_pages_fast+0x621/0x9d0 Code: <48> 81 7a 68 80 08 04 bc 0f 85 21 ff ff 8 89 c7 be RSP: 0018:ffffaa90087679b0 EFLAGS: 00010046 RAX: ffffe3f37905b900 RBX: 00007f2dd561e000 RCX: ffffe3f37905b934 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffe3f37905b900 ... CR2: 0000000000000068 CR3: 00000004c5898003 CR4: 00000000001726e0 Call Trace: get_user_pages_fast_only+0x13/0x20 hva_to_pfn+0xa9/0x3e0 try_async_pf+0xa1/0x270 direct_page_fault+0x113/0xad0 kvm_mmu_page_fault+0x69/0x680 vmx_handle_exit+0xe1/0x5d0 kvm_arch_vcpu_ioctl_run+0xd81/0x1c70 kvm_vcpu_ioctl+0x267/0x670 __x64_sys_ioctl+0x83/0xa0 do_syscall_64+0x56/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0018 7th percentileScored 2026-11-07
Fix Partial Linux (Linux): 5.14.15, 5.15Red Hat: 2 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux5.14 and later5.14.15, 5.15Patch availableCNA
  • Linux VendorLinux Affected 5.14 and later Fixed in 5.14.15, 5.15 Patch available CNA

CPE configurations NVD · 7

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*5.14 to before 5.14.15VulnerableLinux
cpe:2.3:o:linux:linux_kernel:5.15:rc1:*:*:*:*:*:*5.15 rc1VulnerableLinux
cpe:2.3:o:linux:linux_kernel:5.15:rc2:*:*:*:*:*:*5.15 rc2VulnerableLinux
cpe:2.3:o:linux:linux_kernel:5.15:rc3:*:*:*:*:*:*5.15 rc3VulnerableLinux
cpe:2.3:o:linux:linux_kernel:5.15:rc4:*:*:*:*:*:*5.15 rc4VulnerableLinux
cpe:2.3:o:linux:linux_kernel:5.15:rc5:*:*:*:*:*:*5.15 rc5VulnerableLinux
cpe:2.3:o:linux:linux_kernel:5.15:rc6:*:*:*:*:*:*5.15 rc6VulnerableLinux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 5.14 to before 5.14.15 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:5.15:rc1:*:*:*:*:*:* Versions 5.15 rc1 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:5.15:rc2:*:*:*:*:*:* Versions 5.15 rc2 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:5.15:rc3:*:*:*:*:*:* Versions 5.15 rc3 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:5.15:rc4:*:*:*:*:*:* Versions 5.15 rc4 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:5.15:rc5:*:*:*:*:*:* Versions 5.15 rc5 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:5.15:rc6:*:*:*:*:*:* Versions 5.15 rc6 Vulnerable ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 5.14.15, 5.15

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 7AffectedNo fix planned: Out of support scope
Not affected: 2 products
  • Red Hat Enterprise Linux 8
  • Red Hat Enterprise Linux 9

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-47463
  2. 2026-10-03 Alias added: GHSA-xjr2-g37g-hrjm

References

Patch 2

  • TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
  • TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
  • TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
  • TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
  • TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
See all 15278 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences