In the Linux kernel, the following vulnerability has been resolved:

powerpc/fixmap: Fix VM debug warning on unmap

Unmapping a fixmap entry is done by calling __set_fixmap()
with FIXMAP_PAGE_CLEAR as flags.

Today, powerpc __set_fixmap() calls map_kernel_page().

map_kernel_page() is not happy when called a second time
for the same page.

WARNING: CPU: 0 PID: 1 at arch/powerpc/mm/pgtable.c:194 set_pte_at+0xc/0x1e8
CPU: 0 PID: 1 Comm: swapper Not tainted 5.16.0-rc3-s3k-dev-01993-g350ff07feb7d-dirty #682
NIP: c0017cd4 LR: c00187f0 CTR: 00000010
REGS: e1011d50 TRAP: 0700 Not tainted (5.16.0-rc3-s3k-dev-01993-g350ff07feb7d-dirty)
MSR: 00029032 <EE,ME,IR,DR,RI> CR: 42000208 XER: 00000000

GPR00: c0165fec e1011e10 c14c0000 c0ee2550 ff800000 c0f3d000 00000000 c001686c
GPR08: 00001000 b00045a9 00000001 c0f58460 c0f50000 00000000 c0007e10 00000000
GPR16: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
GPR24: 00000000 00000000 c0ee2550 00000000 c0f57000 00000ff8 00000000 ff800000
NIP [c0017cd4] set_pte_at+0xc/0x1e8
LR [c00187f0] map_kernel_page+0x9c/0x100
Call Trace:
[e1011e10] [c0736c68] vsnprintf+0x358/0x6c8 (unreliable)
[e1011e30] [c0165fec] __set_fixmap+0x30/0x44
[e1011e40] [c0c13bdc] early_iounmap+0x11c/0x170
[e1011e70] [c0c06cb0] ioremap_legacy_serial_console+0x88/0xc0
[e1011e90] [c0c03634] do_one_initcall+0x80/0x178
[e1011ef0] [c0c0385c] kernel_init_freeable+0xb4/0x250
[e1011f20] [c0007e34] kernel_init+0x24/0x140
[e1011f30] [c0016268] ret_from_kernel_thread+0x5c/0x64
Instruction dump:
7fe3fb78 48019689 80010014 7c630034 83e1000c 5463d97e 7c0803a6 38210010
4e800020 81250000 712a0001 41820008 <0fe00000> 9421ffe0 93e1001c 48000030

Implement unmap_kernel_page() which clears an existing pte.

No CVSS v4.0

Attack Vector Local

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

The EPSS score is 0.00017.

Exploitation none

Automatable no

Technical Impact partial

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions
Linux Linux unaffected
Version Status Constraints
265c3491c4bc8d40587996d6ee2f447a7ccfb4f3 affected < 67baac10dd5ad1e9f50e8f2659984b3b0728d54e
265c3491c4bc8d40587996d6ee2f447a7ccfb4f3 affected < 43ae0ccc4d2722b833fb59b905af129428e06d03
265c3491c4bc8d40587996d6ee2f447a7ccfb4f3 affected < 033fd42c18d9b2121595b6f1e8419a115f9ac5b7
265c3491c4bc8d40587996d6ee2f447a7ccfb4f3 affected < aec982603aa8cc0a21143681feb5f60ecc69d718
Linux Linux affected
Version Status Constraints
5.5 affected —
0 unaffected < 5.5
5.10.101 unaffected ≤ 5.10.*
5.15.24 unaffected ≤ 5.15.*
5.16.10 unaffected ≤ 5.16.*
5.17 unaffected ≤ *

Configuration 1 [-]

OR cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.17:rc1:*:*:*:*:*:*
Package CPE Advisory Released Date
Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions
kernel-0:5.14.0-70.117.1.el9_0 cpe:/a:redhat:rhel_e4s:9.0 RHSA-2024:6991 2024-09-24T00:00:00Z

No data.

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Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References
Link Providers
https://git.kernel.org/stable/c/033fd42c18d9b2121595b6f1e8419a115f9ac5b7 cve-icon cve-icon
https://git.kernel.org/stable/c/43ae0ccc4d2722b833fb59b905af129428e06d03 cve-icon cve-icon
https://git.kernel.org/stable/c/67baac10dd5ad1e9f50e8f2659984b3b0728d54e cve-icon cve-icon
https://git.kernel.org/stable/c/aec982603aa8cc0a21143681feb5f60ecc69d718 cve-icon cve-icon
https://lore.kernel.org/linux-cve-announce/2024071645-CVE-2021-47623-407f@gregkh/T cve-icon
https://nvd.nist.gov/vuln/detail/CVE-2021-47623 cve-icon
https://www.cve.org/CVERecord?id=CVE-2021-47623 cve-icon
History

Fri, 03 Oct 2025 14:45:00 +0000

Type Values Removed Values Added
First Time appeared Linux
Linux linux Kernel
Weaknesses NVD-CWE-noinfo
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.17:rc1:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
Metrics cvssV3_1

{'score': 4.4, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H'}

 cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

Thu, 19 Dec 2024 08:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Tue, 24 Sep 2024 06:30:00 +0000

Type Values Removed Values Added
First Time appeared Redhat
Redhat rhel E4s
CPEs cpe:/a:redhat:rhel_e4s:9.0
Vendors & Products Redhat
Redhat rhel E4s

Thu, 12 Sep 2024 08:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Wed, 11 Sep 2024 13:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2025-12-18T11:38:16.893Z

Reserved: 2024-07-16T11:26:52.956Z

Link: CVE-2021-47623

cve-icon Vulnrichment

Updated: 2024-08-04T05:47:40.568Z

cve-icon NVD

Status : Analyzed

Published: 2024-07-16T12:15:02.483

Modified: 2025-10-03T14:30:26.893

Link: CVE-2021-47623

cve-icon Redhat

Severity : Low

Publid Date: 2024-07-16T00:00:00Z

Links: CVE-2021-47623 - Bugzilla

cve-icon OpenCVE Enrichment

No data.

Weaknesses