CVE-2025-40012: Linux kernel · net/smc: fix warning in smc_rx_splice() when calling get_page()
Source GCVE Database
Not known to be exploited · CVSS 7.8 High.
Data as of 25 Oct 2026, 19:02 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 8% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
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 20 Oct 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: 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 2026-10-25.
What to do
AI-suggested
The vulnerability description indicates that a fix has been implemented by changing the memory allocation method in the kernel source code. Users should monitor official Linux kernel releases and apply updates that include this fix once available.
Description
A use-after-free vulnerability in the Linux kernel's smc_rx_splice() function was identified and resolved. The issue arises because DMB buffers allocated with kzalloc() are not page-backed, triggering warnings and preventing proper reference counting when passed to get_page(). This can lead to use-after-free if the memory is released prematurely. The fix involves using folio_alloc() to ensure buffers are page-backed and safe for get_page().
References
- nvd.nist.gov/vuln/detail/CVE-2025-40012 (opens in a new tab)
- git.kernel.org/stable/c/14fc4fdae42e34d7ee871b292ac2ecc61c2c5de7 (opens in a new tab)
- git.kernel.org/stable/c/a35c04de2565db191726b5741e6b66a35002c652 (opens in a new tab)
- git.kernel.org/stable/c/d5411685dc2f6ac7bdf01a0a204d56cae38c6cf6 (opens in a new tab)