CVE-2026-43185
published 2026-05-06CVE-2026-43185: In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix signededness bug in smb_direct_prepare_negotiation()…
PriorityP352critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EPSS
0.62%
46.2th percentile
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix signededness bug in smb_direct_prepare_negotiation()
smb_direct_prepare_negotiation() casts an unsigned __u32 value
from sp->max_recv_size and req->preferred_send_size to a signed
int before computing min_t(int, ...). A maliciously provided
preferred_send_size of 0x80000000 will return as smaller than
max_recv_size, and then be used to set the maximum allowed
alowed receive size for the next message.
By sending a second message with a large value (>1420 bytes)
the attacker can then achieve a heap buffer overflow.
This fix replaces min_t(int, ...) with min_t(u32)
Affected
11 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| linux | linux | — | — |
| linux | linux | >= 0626e6641f6b467447c81dd7678a69c66f7746cf < ceae058eb707ddd0d68f0872f9d9f23b7c30c37b | ceae058eb707ddd0d68f0872f9d9f23b7c30c37b |
| linux | linux | >= 0626e6641f6b467447c81dd7678a69c66f7746cf < 55abc475d096da4a5356b6efb0cfdc6156bc1550 | 55abc475d096da4a5356b6efb0cfdc6156bc1550 |
| linux | linux | >= 0626e6641f6b467447c81dd7678a69c66f7746cf < 6b4f875aac344cdd52a1f34cc70ed2f874a65757 | 6b4f875aac344cdd52a1f34cc70ed2f874a65757 |
| linux | linux_kernel | — | — |
| linux | linux_kernel | >= 5.15 < 6.18.16 | 6.18.16 |
| linux | linux_kernel | >= 6.19 < 6.19.6 | 6.19.6 |
| ubuntu | linux-gcp-5.15 | — | — |
| ubuntu | linux-hwe-6.17 | — | — |
| ubuntu | linux-intel-iotg-5.15 | — | — |
| ubuntu | linux-raspi | — | — |
CVSS provenance
nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
vendor_ubuntu7.1HIGH
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Ubuntu
Linux kernel (Raspberry Pi) vulnerabilities
vendor_ubuntu·2026-07-15·CVSS 7.1
CVE-2026-31682 [HIGH] Linux kernel (Raspberry Pi) vulnerabilities
Title: Linux kernel (Raspberry Pi) 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:
- ARM64 architecture;
- Block layer subsystem;
- Cryptographic API;
- DMA engine subsystem;
- InfiniBand drivers;
- STMicroelectronics network drivers;
- Network drivers;
- NVME drivers;
- SCSI subsystem;
- USB over IP driver;
- File systems infrastructure;
- Ext4 file system;
- Network file system (NFS) server daemon;
- SMB network file system;
- Kernel thread helper (kthread);
- IPv6 networking;
- Tracing infrastructure;
- Kernel exit() syscall;
- Scatterlist API;
- B.A.T.M.A.N. meshing protocol
Ubuntu
Linux kernel vulnerabilities
vendor_ubuntu·2026-07-15·CVSS 4.7
CVE-2026-23190 [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:
- RISC-V architecture;
- Cryptographic API;
- InfiniBand drivers;
- IOMMU subsystem;
- Network drivers;
- STMicroelectronics network drivers;
- NVME drivers;
- x86 platform drivers;
- SCSI subsystem;
- SPI subsystem;
- TCM subsystem;
- USB over IP driver;
- File systems infrastructure;
- HFS+ file system;
- Network file system (NFS) server daemon;
- SMB network file system;
- IPv6 networking;
- Tracing infrastructure;
- Timer subsystem;
- B.A.T.M.A.N. meshing protocol;
- Bluetooth subsystem;
- Ethernet bridge;
-
Ubuntu
Linux kernel (HWE) vulnerabilities
vendor_ubuntu·2026-07-15·CVSS 7.1
CVE-2026-43341 [HIGH] Linux kernel (HWE) vulnerabilities
Title: Linux kernel (HWE) 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:
- ARM64 architecture;
- Block layer subsystem;
- Cryptographic API;
- DMA engine subsystem;
- InfiniBand drivers;
- STMicroelectronics network drivers;
- Network drivers;
- NVME drivers;
- SCSI subsystem;
- USB over IP driver;
- File systems infrastructure;
- Ext4 file system;
- Network file system (NFS) server daemon;
- SMB network file system;
- Kernel thread helper (kthread);
- IPv6 networking;
- Tracing infrastructure;
- Kernel exit() syscall;
- Scatterlist API;
- B.A.T.M.A.N. meshing protocol;
- Ether
Red Hat
kernel: ksmbd: fix signededness bug in smb_direct_prepare_negotiation()
vendor_redhat·2026-05-06
CVE-2026-43185 CWE-681 kernel: ksmbd: fix signededness bug in smb_direct_prepare_negotiation()
kernel: ksmbd: fix signededness bug in smb_direct_prepare_negotiation()
A flaw was found in ksmbd within the Linux kernel. A remote attacker can exploit a signedness bug in the smb_direct_prepare_negotiation() function by sending a specially crafted preferred_send_size value during SMB direct negotiation. This manipulation leads to an incorrect size calculation, allowing a subsequent large message to trigger a heap buffer overflow. A successful exploit could result in arbitrary code execution or 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 Ent
GHSA
GHSA-vcg7-gx5w-x44c: In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix signededness bug in smb_direct_prepare_negotiation()
smb_direct_prepa
ghsa_unreviewed·2026-05-06
CVE-2026-43185 GHSA-vcg7-gx5w-x44c: In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix signededness bug in smb_direct_prepare_negotiation()
smb_direct_prepa
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix signededness bug in smb_direct_prepare_negotiation()
smb_direct_prepare_negotiation() casts an unsigned __u32 value
from sp->max_recv_size and req->preferred_send_size to a signed
int before computing min_t(int, ...). A maliciously provided
preferred_send_size of 0x80000000 will return as smaller than
max_recv_size, and then be used to set the maximum allowed
alowed receive size for the next message.
By sending a second message with a large value (>1420 bytes)
the attacker can then achieve a heap buffer overflow.
This fix replaces min_t(int, ...) with min_t(u32)
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2026-43185 kernel: ksmbd: fix signededness bug in smb_direct_prepare_negotiation()
bugzilla·2026-05-06
CVE-2026-43185 CVE-2026-43185 kernel: ksmbd: fix signededness bug in smb_direct_prepare_negotiation()
CVE-2026-43185 kernel: ksmbd: fix signededness bug in smb_direct_prepare_negotiation()
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix signededness bug in smb_direct_prepare_negotiation()
smb_direct_prepare_negotiation() casts an unsigned __u32 value
from sp->max_recv_size and req->preferred_send_size to a signed
int before computing min_t(int, ...). A maliciously provided
preferred_send_size of 0x80000000 will return as smaller than
max_recv_size, and then be used to set the maximum allowed
alowed receive size for the next message.
By sending a second message with a large value (>1420 bytes)
the attacker can then achieve a heap buffer overflow.
This fix replaces min_t(int, ...) with min_t(u32)
Discussion:
Upstream advisory:
https://lore.kernel.org/lin
Rapid7
Patch Tuesday - May 2026
blogs_rapid7·2026-05-13·CVSS 10.0
CVE-2026-41089 [CRITICAL] Patch Tuesday - May 2026
Microsoft is publishing 137 vulnerabilities on May 2026 Patch Tuesday . Microsoft is not aware of exploitation in the wild or public disclosure for any of these vulnerabilities. So far this month, Microsoft has provided patches to address 133 browser vulnerabilities, which are not included in the Patch Tuesday count above.
## Windows Netlogon: critical RCE
Anyone responsible for securing a domain controller should prioritize remediation of CVE-2026-41089 , which is a critical stack-based buffer overflow in Windows Netlogon with a CVSS v3 base score of 9.8. Exploitation leads to execution in the context of the Netlogon service, so that’s SYSTEM privileges on the domain controller. For most pentesters, that’s the point at which the customer report more or less writes itself. No privileges
2026-05-06
Published