What’s Vulnerable › Vulnerabilities

CVE-2026-31608: smb: server: avoid double-free in smb_direct_free_sendmsg after smb_direct_flush_send_list()

• Severity: critical (CVSS 9.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.5% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-04-24 · updated 2026-06-17
• Weakness: CWE-415

Description

In the Linux kernel, the following vulnerability has been resolved: smb: server: avoid double-free in smb_direct_free_sendmsg after smb_direct_flush_send_list() smb_direct_flush_send_list() already calls smb_direct_free_sendmsg(), so we should not call it again after post_sendmsg() moved it to the batch list.

Affected products

• Linux kernel: before 6.18.24; from 6.19 before 6.19.14; from 7.0 before 7.0.1 — fixed in 6.18.24, 6.19.14, 7.0.1

How to fix

Upgrade to a fixed version: Linux kernel 6.18.24, 6.19.14, 7.0.1. Check the vendor advisory for mitigations.

References

• https://git.kernel.org/stable/c/2ba03f46132b0d1a7bafb86e1ef61951a2254023
• https://git.kernel.org/stable/c/6968c91fab05b8fc4d6700e0cf34472bb422df25
• https://git.kernel.org/stable/c/830de6eeb9db4cb7e758201fb99328ef4ca4b032
• https://git.kernel.org/stable/c/84ff995ae826aa6bbcc6c7b9ea569ff67c021d72

Get alerted when CVE-2026-31608 or the next vulnerability affects your stack