CVE-2025-37777: Linux kernel · ksmbd: fix use-after-free in __smb2_lease_break_noti()
Source GCVE Database
Not known to be exploited · CVSS 7.8 High.
Data as of 13 Nov 2026, 18:50 UTC
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 1 May 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 13 Nov 2026.
What to do
AI-suggested
The vulnerability has been resolved in the Linux kernel by adjusting the resource free timing to ksmbd_conn_free. Users and administrators should apply the official Linux kernel updates that include this fix.
Description
CVE-2025-37777 is a use-after-free vulnerability in the Linux kernel's ksmbd component, specifically in the __smb2_lease_break_noti() function. The issue arises because the tcp_transport resource is freed prematurely while the ksmbd connection may still be referenced asynchronously, leading to a use-after-free condition when ksmbd_conn_write is called. This vulnerability has a high severity score of 7.8 and impacts confidentiality, integrity, and availability.
References
- nvd.nist.gov/vuln/detail/CVE-2025-37777 (opens in a new tab)
- git.kernel.org/stable/c/1aec4d14cf81b7b3e7b69eb1cfa94144eed7138e (opens in a new tab)
- git.kernel.org/stable/c/1da8bd9a10ecd718692732294d15fd801c0eabb5 (opens in a new tab)
- git.kernel.org/stable/c/21a4e47578d44c6b37c4fc4aba8ed7cc8dbb13de (opens in a new tab)
- git.kernel.org/stable/c/e59796fc80603bcd8569d4d2e10b213c1918edb4 (opens in a new tab)