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TI-2026-31364 Aliases CVE-2026-43185GHSA-vcg7-gx5w-x44c

ksmbd: fix signededness bug in smb_direct_prepare_negotiation()

Priority MEDIUM 44CWE-674Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-674.

Summary

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)

Why it matters now

EPSS 0.00887 59th percentileScored 2026-11-07
Fix Fixed Linux (Linux): 6.1.191, 6.6.160, 6.12.114 +3

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux5.15 and later6.1.191, 6.6.160, 6.12.114, 6.18.16, 6.19.6, 7.0Patch availableCNA
  • Linux VendorLinux Affected 5.15 and later Fixed in 6.1.191, 6.6.160, 6.12.114, 6.18.16, 6.19.6, 7.0 Patch available CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*5.15 to before 6.18.16; 6.19 to before 6.19.6VulnerableLinux
cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*7.0 rc1VulnerableLinux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 5.15 to before 6.18.16; 6.19 to before 6.19.6 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:* Versions 7.0 rc1 Vulnerable ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 6.1.191, 6.6.160, 6.12.114, 6.18.16, 6.19.6, 7.0

Vendor assessments

Red Hat

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

Not affected: 5 products
  • Red Hat Enterprise Linux 10
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8
  • Red Hat Enterprise Linux 9

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-43185
  2. 2026-10-03 Alias added: GHSA-vcg7-gx5w-x44c
  3. 2026-10-20 Affected versions changed · Red Hat
  4. 2026-10-21 Fix available: Linux/Linux@56eab82fa6fb5ca024b0514e249d40d9b23ee5a7, Linux/[email protected], Linux/[email protected] +1 · CNA
  5. 2026-10-21 2 new references · CNA
  6. 2026-10-30 Fix available: Linux/Linux@1c268fd2f59dc9ccb2c2a7d1f439b232dbe1c06c, Linux/[email protected] · CNA
  7. 2026-10-30 1 new reference · CNA

References

Patch 3

Other 3

  • 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