CVE-2026-64397
published 2026-07-25CVE-2026-64397: In the Linux kernel, the following vulnerability has been resolved: ksmbd: serialize QUERY_DIRECTORY requests per file smb2_query_dir() stores a pointer to its…
PriorityP355critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EPSS
0.48%
40.2th percentile
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: serialize QUERY_DIRECTORY requests per file
smb2_query_dir() stores a pointer to its stack-allocated private data in
the ksmbd_file readdir_data. Concurrent QUERY_DIRECTORY requests using the
same file handle can overwrite this pointer while an iterate_dir() callback
is still using it, resulting in a stack use-after-free.
Add a per-file mutex and hold it while accessing the shared directory
enumeration state. The lock covers scan restart, dot entry state,
readdir_data setup and iteration, and response construction. This prevents
another request from replacing readdir_data.private before the current
request has finished using it and also serializes the shared file position.
Affected
37 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| linux | linux | — | — |
| linux | linux | >= e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 < 1426fd79102539bc0ab5c8fced047ad4313b9908 | 1426fd79102539bc0ab5c8fced047ad4313b9908 |
| linux | linux | >= e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 < 2a64dbf9c739ddf7a25a066507597bf89f8f73d2 | 2a64dbf9c739ddf7a25a066507597bf89f8f73d2 |
| linux | linux | >= e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 < 64dac2d486ec1eb18dc00968b16a230b6b75ec24 | 64dac2d486ec1eb18dc00968b16a230b6b75ec24 |
| linux | linux | >= e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 < a1d5d31cad593ea5e1b637f2f39c9ef6d09d1199 | a1d5d31cad593ea5e1b637f2f39c9ef6d09d1199 |
| linux | linux | >= e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 < fd22b039a5a05bc1d6818e9dcd1001fb432a829d | fd22b039a5a05bc1d6818e9dcd1001fb432a829d |
| linux | linux | >= e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 < be6d26bf27499977c746abc163659915082348d8 | be6d26bf27499977c746abc163659915082348d8 |
| linux | linux_kernel | >= 5.15 < 6.1.178 | 6.1.178 |
| linux | linux_kernel | >= 6.13 < 6.18.39 | 6.18.39 |
| linux | linux_kernel | >= 6.19 < 7.1.4 | 7.1.4 |
| linux | linux_kernel | >= 6.2 < 6.6.145 | 6.6.145 |
| linux | linux_kernel | >= 6.7 < 6.12.96 | 6.12.96 |
| ubuntu | linux | — | — |
| ubuntu | linux-aws | — | — |
| ubuntu | linux-aws-7.0 | — | — |
| ubuntu | linux-aws-fips | — | — |
| ubuntu | linux-azure | — | — |
| ubuntu | linux-azure-7.0 | — | — |
| ubuntu | linux-azure-fde | — | — |
| ubuntu | linux-azure-fips | — | — |
| ubuntu | linux-fips | — | — |
| ubuntu | linux-gcp | — | — |
| ubuntu | linux-gcp-7.0 | — | — |
| ubuntu | linux-gcp-fips | — | — |
| ubuntu | linux-gke | — | — |
CVSS provenance
nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
vendor_redhat9.8CRITICAL
vendor_ubuntu9.1CRITICAL
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Ubuntu
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CVE-2026-72197 [MEDIUM] Linux kernel (Azure) vulnerabilities
Title: Linux kernel (Azure) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some AMD processors did not properly perform Reverse
Map Table (RMP) checks when the IOMMU accessed certain host buffers. A
local attacker with hypervisor access could possibly use this to trigger an
out-of-bounds condition and compromise the integrity of SEV-SNP guest
memory. (CVE-2023-20585)
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:
- NVDIMM (Non-Volatile Memory Device) drivers;
- Handshake API;
- ARM32 architecture;
- ARM64 architecture;
- MIPS architecture;
- PowerPC architecture;
- RISC-V architecture;
- S390 archite
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vendor_ubuntu·2026-10-13·CVSS 5.6
CVE-2026-72213 [MEDIUM] Linux kernel vulnerabilities
Title: Linux kernel vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some AMD processors did not properly perform Reverse
Map Table (RMP) checks when the IOMMU accessed certain host buffers. A
local attacker with hypervisor access could possibly use this to trigger an
out-of-bounds condition and compromise the integrity of SEV-SNP guest
memory. (CVE-2023-20585)
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:
- NVDIMM (Non-Volatile Memory Device) drivers;
- Handshake API;
- ARM32 architecture;
- ARM64 architecture;
- MIPS architecture;
- PowerPC architecture;
- RISC-V architecture;
- S390 architecture;
-
Ubuntu
Linux kernel (Oracle) vulnerabilities
vendor_ubuntu·2026-09-29·CVSS 9.1
CVE-2026-64191 [CRITICAL] Linux kernel (Oracle) vulnerabilities
Title: Linux kernel (Oracle) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some Arm processors could complete a broadcast
translation lookaside buffer (TLB) invalidation before memory writes made
through the invalidated translation were globally observed. A local
attacker could possibly use this to write to memory after permission to do
so had been revoked, bypassing memory protections or escalating privileges.
(CVE-2025-10263)
It was discovered that some AMD Zen 2 processors did not properly isolate
shared resources in the operation cache. A local attacker could possibly
use this issue to corrupt instructions executed at a higher privilege
level, resulting in privilege escalation. (CVE-2025-54518)
Several security issues were d
Ubuntu
Linux kernel vulnerabilities
vendor_ubuntu·2026-09-22·CVSS 9.1
CVE-2026-63869 [CRITICAL] Linux kernel vulnerabilities
Title: Linux kernel vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some Arm processors could complete a broadcast
translation lookaside buffer (TLB) invalidation before memory writes made
through the invalidated translation were globally observed. A local
attacker could possibly use this to write to memory after permission to do
so had been revoked, bypassing memory protections or escalating privileges.
(CVE-2025-10263)
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:
- ARM64 architecture;
- User-space API (UAPI);
- Kernel build system;
- ARM32 architecture;
- RISC-V architecture;
- S390 architecture;
Ubuntu
Linux kernel (Azure) vulnerabilities
vendor_ubuntu·2026-09-22·CVSS 9.1
CVE-2026-52938 [CRITICAL] Linux kernel (Azure) vulnerabilities
Title: Linux kernel (Azure) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some Arm processors could complete a broadcast
translation lookaside buffer (TLB) invalidation before memory writes made
through the invalidated translation were globally observed. A local
attacker could possibly use this to write to memory after permission to do
so had been revoked, bypassing memory protections or escalating privileges.
(CVE-2025-10263)
It was discovered that some AMD Zen 2 processors did not properly isolate
shared resources in the operation cache. A local attacker could possibly
use this issue to corrupt instructions executed at a higher privilege
level, resulting in privilege escalation. (CVE-2025-54518)
Several security issues were di
Ubuntu
Linux kernel (NVIDIA BaseOS) vulnerabilities
vendor_ubuntu·2026-09-22
CVE-2026-64504 Linux kernel (NVIDIA BaseOS) vulnerabilities
Title: Linux kernel (NVIDIA BaseOS) 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:
- User-space API (UAPI);
- Kernel build system;
- ARM32 architecture;
- ARM64 architecture;
- RISC-V architecture;
- S390 architecture;
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
- Compute Acceleration Framework;
- Intel NPU Driver;
- ACPI drivers;
- Android drivers;
- Drivers core;
- Compressed RAM block device driver;
- Bluetooth drivers;
- Character device driver;
- Hardware random number generator core;
- CPU frequency scaling framework;
- Hardware crypto device drivers
Ubuntu
Linux kernel (IBM) vulnerabilities
vendor_ubuntu·2026-09-21·CVSS 9.1
CVE-2026-63869 [CRITICAL] Linux kernel (IBM) vulnerabilities
Title: Linux kernel (IBM) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some Arm processors could complete a broadcast
translation lookaside buffer (TLB) invalidation before memory writes made
through the invalidated translation were globally observed. A local
attacker could possibly use this to write to memory after permission to do
so had been revoked, bypassing memory protections or escalating privileges.
(CVE-2025-10263)
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:
- ARM64 architecture;
- User-space API (UAPI);
- Kernel build system;
- ARM32 architecture;
- RISC-V architecture;
- S390 architec
Ubuntu
Linux kernel (NVIDIA Tegra) vulnerabilities
vendor_ubuntu·2026-09-18·CVSS 9.1
CVE-2026-53358 [CRITICAL] Linux kernel (NVIDIA Tegra) vulnerabilities
Title: Linux kernel (NVIDIA Tegra) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some Arm processors could complete a broadcast
translation lookaside buffer (TLB) invalidation before memory writes made
through the invalidated translation were globally observed. A local
attacker could possibly use this to write to memory after permission to do
so had been revoked, bypassing memory protections or escalating privileges.
(CVE-2025-10263)
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:
- ARM64 architecture;
- User-space API (UAPI);
- Kernel build system;
- ARM32 architecture;
- PowerPC architecture;
- RIS
Ubuntu
Linux kernel (Raspberry Pi) vulnerabilities
vendor_ubuntu·2026-09-18·CVSS 9.1
CVE-2026-64504 [CRITICAL] Linux kernel (Raspberry Pi) vulnerabilities
Title: Linux kernel (Raspberry Pi) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some Arm processors could complete a broadcast
translation lookaside buffer (TLB) invalidation before memory writes made
through the invalidated translation were globally observed. A local
attacker could possibly use this to write to memory after permission to do
so had been revoked, bypassing memory protections or escalating privileges.
(CVE-2025-10263)
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:
- ARM64 architecture;
- User-space API (UAPI);
- Kernel build system;
- ARM32 architecture;
- RISC-V architecture;
- S390
Ubuntu
Linux kernel (NVIDIA) vulnerabilities
vendor_ubuntu·2026-09-15
CVE-2026-63869 Linux kernel (NVIDIA) vulnerabilities
Title: Linux kernel (NVIDIA) 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:
- User-space API (UAPI);
- Kernel build system;
- ARM32 architecture;
- ARM64 architecture;
- RISC-V architecture;
- S390 architecture;
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
- Compute Acceleration Framework;
- Intel NPU Driver;
- ACPI drivers;
- Android drivers;
- Drivers core;
- Compressed RAM block device driver;
- Bluetooth drivers;
- Character device driver;
- Hardware random number generator core;
- CPU frequency scaling framework;
- Hardware crypto device drivers;
- Buf
Ubuntu
Linux kernel (GCP) vulnerabilities
vendor_ubuntu·2026-09-07·CVSS 9.1
CVE-2026-52938 [CRITICAL] Linux kernel (GCP) vulnerabilities
Title: Linux kernel (GCP) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some Arm processors could complete a broadcast
translation lookaside buffer (TLB) invalidation before memory writes made
through the invalidated translation were globally observed. A local
attacker could possibly use this to write to memory after permission to do
so had been revoked, bypassing memory protections or escalating privileges.
(CVE-2025-10263)
It was discovered that some AMD Zen 2 processors did not properly isolate
shared resources in the operation cache. A local attacker could possibly
use this issue to corrupt instructions executed at a higher privilege
level, resulting in privilege escalation. (CVE-2025-54518)
Several security issues were disc
Ubuntu
Linux kernel vulnerabilities
vendor_ubuntu·2026-09-07·CVSS 9.1
CVE-2026-64504 [CRITICAL] Linux kernel vulnerabilities
Title: Linux kernel vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some Arm processors could complete a broadcast
translation lookaside buffer (TLB) invalidation before memory writes made
through the invalidated translation were globally observed. A local
attacker could possibly use this to write to memory after permission to do
so had been revoked, bypassing memory protections or escalating privileges.
(CVE-2025-10263)
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:
- ARM64 architecture;
- User-space API (UAPI);
- Kernel build system;
- ARM32 architecture;
- RISC-V architecture;
- S390 architecture;
Ubuntu
Linux kernel (OEM) vulnerabilities
vendor_ubuntu·2026-09-07·CVSS 9.1
CVE-2026-63869 [CRITICAL] Linux kernel (OEM) vulnerabilities
Title: Linux kernel (OEM) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some Arm processors could complete a broadcast
translation lookaside buffer (TLB) invalidation before memory writes made
through the invalidated translation were globally observed. A local
attacker could possibly use this to write to memory after permission to do
so had been revoked, bypassing memory protections or escalating privileges.
(CVE-2025-10263)
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:
- ARM64 architecture;
- User-space API (UAPI);
- Kernel build system;
- ARM32 architecture;
- RISC-V architecture;
- S390 architec
Red Hat
kernel: ksmbd: serialize QUERY_DIRECTORY requests per file
vendor_redhat·2026-07-25·CVSS 9.8
CVE-2026-64397 [CRITICAL] CWE-562 kernel: ksmbd: serialize QUERY_DIRECTORY requests per file
kernel: ksmbd: serialize QUERY_DIRECTORY requests per file
A flaw was found in the Linux kernel's ksmbd (kernel Server Message Block daemon) component. Concurrent directory query requests using the same file handle can lead to a stack use-after-free vulnerability. This occurs because smb2_query_dir() stores a pointer to stack-allocated data that can be overwritten by another request while still in use. An attacker could exploit this to cause a denial of service.
Package: kernel (Red Hat Enterprise Linux 10) - Not affected
Package: kernel (Red Hat Enterprise Linux 6) - Not affected
Package: kernel (Red Hat Enterprise Linux 7) - Not affected
Package: kernel-rt (Red Hat Enterprise Linux 7) - Not affected
Package: kernel (Red Hat Enterprise Linux 8) - Not affected
Package: kernel-rt (Re
VulDB
Linux Kernel up to 7.1.3 Ksmbd smb2_query_dir use after free (Nessus ID 329921)
vuldb·2026-07-27
CVE-2026-64397 Linux Kernel up to 7.1.3 Ksmbd smb2_query_dir use after free (Nessus ID 329921)
A vulnerability, which was classified as very critical, has been found in Linux Kernel up to 6.1.177/6.6.144/6.12.95/6.18.38/7.1.3. This affects the function smb2_query_dir of the component Ksmbd. This manipulation causes use after free.
The identification of this vulnerability is CVE-2026-64397. It is possible to initiate the attack remotely. There is no exploit available.
It is advisable to upgrade the affected component.
GHSA
In the Linux kernel, the following vulnerability has been resolved: ksmbd: serialize QUERY_DIRECTORY requests per file smb2_query_dir() stores a pointer to its stack-allocated private data in the ks
ghsa_unreviewed·2026-07-25
CVE-2026-64397 In the Linux kernel, the following vulnerability has been resolved: ksmbd: serialize QUERY_DIRECTORY requests per file smb2_query_dir() stores a pointer to its stack-allocated private data in the ks
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: serialize QUERY_DIRECTORY requests per file
smb2_query_dir() stores a pointer to its stack-allocated private data in
the ksmbd_file readdir_data. Concurrent QUERY_DIRECTORY requests using the
same file handle can overwrite this pointer while an iterate_dir() callback
is still using it, resulting in a stack use-after-free.
Add a per-file mutex and hold it while accessing the shared directory
enumeration state. The lock covers scan restart, dot entry state,
readdir_data setup and iteration, and response construction. This prevents
another request from replacing readdir_data.private before the current
request has finished using it and also serializes the shared file position.
No detection rules found.
No public exploits indexed.
https://git.kernel.org/stable/c/1426fd79102539bc0ab5c8fced047ad4313b9908https://git.kernel.org/stable/c/2a64dbf9c739ddf7a25a066507597bf89f8f73d2https://git.kernel.org/stable/c/64dac2d486ec1eb18dc00968b16a230b6b75ec24https://git.kernel.org/stable/c/a1d5d31cad593ea5e1b637f2f39c9ef6d09d1199https://git.kernel.org/stable/c/be6d26bf27499977c746abc163659915082348d8https://git.kernel.org/stable/c/fd22b039a5a05bc1d6818e9dcd1001fb432a829d
2026-07-25
Published