CVE-2025-21696
published 2025-02-12CVE-2025-21696: In the Linux kernel, the following vulnerability has been resolved: mm: clear uffd-wp PTE/PMD state on mremap() When mremap()ing a memory region previously…
PriorityP419medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.19%
8.5th percentile
In the Linux kernel, the following vulnerability has been resolved:
mm: clear uffd-wp PTE/PMD state on mremap()
When mremap()ing a memory region previously registered with userfaultfd as
write-protected but without UFFD_FEATURE_EVENT_REMAP, an inconsistency in
flag clearing leads to a mismatch between the vma flags (which have
uffd-wp cleared) and the pte/pmd flags (which do not have uffd-wp
cleared). This mismatch causes a subsequent mprotect(PROT_WRITE) to
trigger a warning in page_table_check_pte_flags() due to setting the pte
to writable while uffd-wp is still set.
Fix this by always explicitly clearing the uffd-wp pte/pmd flags on any
such mremap() so that the values are consistent with the existing clearing
of VM_UFFD_WP. Be careful to clear the logical flag regardless of its
physical form; a PTE bit, a swap PTE bit, or a PTE marker. Cover PTE,
huge PMD and hugetlb paths.
Affected
19 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 6.12.11-1 (forky) | linux 6.12.11-1 (forky) |
| linux | linux | — | — |
| linux | linux | >= 63b2d4174c4ad1f40b48d7138e71bcb564c1fe03 < 310ac886d68de661c3a334198d8604b722d7fdf8 | 310ac886d68de661c3a334198d8604b722d7fdf8 |
| linux | linux | >= 63b2d4174c4ad1f40b48d7138e71bcb564c1fe03 < 0cef0bb836e3cfe00f08f9606c72abd72fe78ca3 | 0cef0bb836e3cfe00f08f9606c72abd72fe78ca3 |
| linux | linux_kernel | — | — |
| linux | linux_kernel | >= 0 < 6.12.11-1 | 6.12.11-1 |
| linux | linux_kernel | >= 0 < 6.12.11-1 | 6.12.11-1 |
| linux | linux_kernel | >= 5.7 < 6.12.11 | 6.12.11 |
| msrc | azl3_kernel_6.6.104.2-4_on_azure_linux_3.0 | — | — |
| msrc | azl3_kernel_6.6.112.1-2_on_azure_linux_3.0 | — | — |
| msrc | azl3_kernel_6.6.117.1-1_on_azure_linux_3.0 | — | — |
| msrc | azl3_kernel_6.6.119.3-1_on_azure_linux_3.0 | — | — |
| msrc | azl3_kernel_6.6.119.3-3_on_azure_linux_3.0 | — | — |
| msrc | azl3_kernel_6.6.121.1-1_on_azure_linux_3.0 | — | — |
| msrc | azl3_kernel_6.6.126.1-1_on_azure_linux_3.0 | — | — |
| msrc | azl3_kernel_6.6.130.1-3_on_azure_linux_3.0 | — | — |
| msrc | azl3_kernel_6.6.96.2-1_on_azure_linux_3.0 | — | — |
| msrc | azl3_kernel_6.6.96.2-2_on_azure_linux_3.0 | — | — |
| msrc | cbl2_kernel_5.15.182.1-1_on_cbl_mariner_2.0 | — | — |
CVSS provenance
nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.5MEDIUM
vendor_debian5.5MEDIUM
vendor_msrc5.5MEDIUM
vendor_redhat5.5MEDIUM
vendor_ubuntu5.5MEDIUM
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Ubuntu
Linux kernel vulnerabilities
vendor_ubuntu·2025-04-23·CVSS 5.5
CVE-2025-21695 [MEDIUM] Linux kernel vulnerabilities
Title: Linux kernel vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that the CIFS network file system implementation in the
Linux kernel did not properly verify the target namespace when handling
upcalls. An attacker could use this to expose sensitive information.
(CVE-2025-2312)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- GPIO subsystem;
- GPU drivers;
- IRQ chip drivers;
- Network drivers;
- Mellanox network drivers;
- x86 platform drivers;
- i.MX PM domains;
- SCSI subsystem;
- USB Serial drivers;
- AFS file system;
- GFS2 file system;
- File systems infrastructure;
- Proc file system;
- SMB networ
Ubuntu
Linux kernel vulnerabilities
vendor_ubuntu·2025-04-23·CVSS 5.5
CVE-2025-21695 [MEDIUM] Linux kernel vulnerabilities
Title: Linux kernel vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- GPIO subsystem;
- GPU drivers;
- IRQ chip drivers;
- Network drivers;
- Mellanox network drivers;
- x86 platform drivers;
- i.MX PM domains;
- SCSI subsystem;
- USB Serial drivers;
- AFS file system;
- GFS2 file system;
- File systems infrastructure;
- Proc file system;
- SMB network file system;
- Timer subsystem;
- Kernel CPU control infrastructure;
- Memory management;
- Networking core;
- Ethtool driver;
- IEEE 802.15.4 subsystem;
- Open vSwitch;
- Network traffic control;
- VMware vSockets driver;
(CVE-20
Red Hat
kernel: mm: clear uffd-wp PTE/PMD state on mremap()
vendor_redhat·2025-02-12·CVSS 5.5
CVE-2025-21696 [MEDIUM] CWE-20 kernel: mm: clear uffd-wp PTE/PMD state on mremap()
kernel: mm: clear uffd-wp PTE/PMD state on mremap()
In the Linux kernel, the following vulnerability has been resolved:
mm: clear uffd-wp PTE/PMD state on mremap()
When mremap()ing a memory region previously registered with userfaultfd as
write-protected but without UFFD_FEATURE_EVENT_REMAP, an inconsistency in
flag clearing leads to a mismatch between the vma flags (which have
uffd-wp cleared) and the pte/pmd flags (which do not have uffd-wp
cleared). This mismatch causes a subsequent mprotect(PROT_WRITE) to
trigger a warning in page_table_check_pte_flags() due to setting the pte
to writable while uffd-wp is still set.
Fix this by always explicitly clearing the uffd-wp pte/pmd flags on any
such mremap() so that the values are consistent with the existing clearing
of VM_UFFD_WP. Be carefu
Microsoft
mm: clear uffd-wp PTE/PMD state on mremap()
vendor_msrc·2025-02-11·CVSS 5.5
CVE-2025-21696 [MEDIUM] mm: clear uffd-wp PTE/PMD state on mremap()
mm: clear uffd-wp PTE/PMD state on mremap()
FAQ: Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability?
One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is composed. Microsoft is committed to transparency in this work which is why we began publishing CSAF/VEX in October 2025. See this blog post for more information. If impact to additional products is identified, we will update the CVE to reflect this.
Mariner: Mariner
Linux: Linux
Customer Action Required: Yes
Debian
CVE-2025-21696: linux - In the Linux kernel, the following vulnerability has been resolved: mm: clear u...
vendor_debian·2025·CVSS 5.5
CVE-2025-21696 [MEDIUM] CVE-2025-21696: linux - In the Linux kernel, the following vulnerability has been resolved: mm: clear u...
In the Linux kernel, the following vulnerability has been resolved: mm: clear uffd-wp PTE/PMD state on mremap() When mremap()ing a memory region previously registered with userfaultfd as write-protected but without UFFD_FEATURE_EVENT_REMAP, an inconsistency in flag clearing leads to a mismatch between the vma flags (which have uffd-wp cleared) and the pte/pmd flags (which do not have uffd-wp cleared). This mismatch causes a subsequent mprotect(PROT_WRITE) to trigger a warning in page_table_check_pte_flags() due to setting the pte to writable while uffd-wp is still set. Fix this by always explicitly clearing the uffd-wp pte/pmd flags on any such mremap() so that the values are consistent with the existing clearing of VM_UFFD_WP. Be careful to clear the logical flag regardless of its physica
OSV
linux, linux-aws, linux-gcp, linux-hwe-6.11, linux-lowlatency, linux-lowlatency-hwe-6.11, linux-oem-6.11, linux-oracle, linux-raspi, linux-realtime vulnerabilities
osv·2025-04-23·CVSS 5.5
[MEDIUM] linux, linux-aws, linux-gcp, linux-hwe-6.11, linux-lowlatency, linux-lowlatency-hwe-6.11, linux-oem-6.11, linux-oracle, linux-raspi, linux-realtime vulnerabilities
linux, linux-aws, linux-gcp, linux-hwe-6.11, linux-lowlatency, linux-lowlatency-hwe-6.11, linux-oem-6.11, linux-oracle, linux-raspi, linux-realtime vulnerabilities
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- GPIO subsystem;
- GPU drivers;
- IRQ chip drivers;
- Network drivers;
- Mellanox network drivers;
- x86 platform drivers;
- i.MX PM domains;
- SCSI subsystem;
- USB Serial drivers;
- AFS file system;
- GFS2 file system;
- File systems infrastructure;
- Proc file system;
- SMB network file system;
- Timer subsystem;
- Kernel CPU control infrastructure;
- Memory management;
- Networking core;
- Ethtool driver;
- IEEE 802.15.4 subsystem;
- Open vSwitch
OSV
linux-azure, linux-azure-6.11 vulnerabilities
osv·2025-04-23·CVSS 5.5
CVE-2025-2312 [MEDIUM] linux-azure, linux-azure-6.11 vulnerabilities
linux-azure, linux-azure-6.11 vulnerabilities
It was discovered that the CIFS network file system implementation in the
Linux kernel did not properly verify the target namespace when handling
upcalls. An attacker could use this to expose sensitive information.
(CVE-2025-2312)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- GPIO subsystem;
- GPU drivers;
- IRQ chip drivers;
- Network drivers;
- Mellanox network drivers;
- x86 platform drivers;
- i.MX PM domains;
- SCSI subsystem;
- USB Serial drivers;
- AFS file system;
- GFS2 file system;
- File systems infrastructure;
- Proc file system;
- SMB network file system;
- Timer subsystem;
- Kernel CPU control i
GHSA
GHSA-6q8c-8rxm-f6fh: In the Linux kernel, the following vulnerability has been resolved:
mm: clear uffd-wp PTE/PMD state on mremap()
When mremap()ing a memory region pre
ghsa_unreviewed·2025-02-12
CVE-2025-21696 [MEDIUM] GHSA-6q8c-8rxm-f6fh: In the Linux kernel, the following vulnerability has been resolved:
mm: clear uffd-wp PTE/PMD state on mremap()
When mremap()ing a memory region pre
In the Linux kernel, the following vulnerability has been resolved:
mm: clear uffd-wp PTE/PMD state on mremap()
When mremap()ing a memory region previously registered with userfaultfd as
write-protected but without UFFD_FEATURE_EVENT_REMAP, an inconsistency in
flag clearing leads to a mismatch between the vma flags (which have
uffd-wp cleared) and the pte/pmd flags (which do not have uffd-wp
cleared). This mismatch causes a subsequent mprotect(PROT_WRITE) to
trigger a warning in page_table_check_pte_flags() due to setting the pte
to writable while uffd-wp is still set.
Fix this by always explicitly clearing the uffd-wp pte/pmd flags on any
such mremap() so that the values are consistent with the existing clearing
of VM_UFFD_WP. Be careful to clear the logical flag regardless of its
phys
OSV
CVE-2025-21696: In the Linux kernel, the following vulnerability has been resolved: mm: clear uffd-wp PTE/PMD state on mremap() When mremap()ing a memory region previ
osv·2025-02-12·CVSS 5.5
CVE-2025-21696 [MEDIUM] CVE-2025-21696: In the Linux kernel, the following vulnerability has been resolved: mm: clear uffd-wp PTE/PMD state on mremap() When mremap()ing a memory region previ
In the Linux kernel, the following vulnerability has been resolved: mm: clear uffd-wp PTE/PMD state on mremap() When mremap()ing a memory region previously registered with userfaultfd as write-protected but without UFFD_FEATURE_EVENT_REMAP, an inconsistency in flag clearing leads to a mismatch between the vma flags (which have uffd-wp cleared) and the pte/pmd flags (which do not have uffd-wp cleared). This mismatch causes a subsequent mprotect(PROT_WRITE) to trigger a warning in page_table_check_pte_flags() due to setting the pte to writable while uffd-wp is still set. Fix this by always explicitly clearing the uffd-wp pte/pmd flags on any such mremap() so that the values are consistent with the existing clearing of VM_UFFD_WP. Be careful to clear the logical flag regardless of its physica
No detection rules found.
No public exploits indexed.
2025-02-12
Published