CVE-2024-40966: Linux kernel · tty: add the option to have a tty reject a new ldisc
Source GCVE Database
Not known to be exploited · CVSS 5.5 Medium.
Data as of 29 Oct 2026, 22:52 UTC
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 12 Jul 2024
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 29 Oct 2026.
Description
In the Linux kernel, the following vulnerability has been resolved: tty: add the option to have a tty reject a new ldisc ... and use it to limit the virtual terminals to just N_TTY. They are kind of special, and in particular, the "con_write()" routine violates the "writes cannot sleep" rule that some ldiscs rely on. This avoids the BUG: sleeping function called from invalid context at kernel/printk/printk.c:2659 when N_GSM has been attached to a virtual console, and gsmld_write() calls con_write() while holding a spinlock, and con_write() then tries to get the console lock.
References
- nvd.nist.gov/vuln/detail/CVE-2024-40966 (opens in a new tab)
- git.kernel.org/stable/c/287b569a5b914903ba7c438a3c0dbc3410ebb409 (opens in a new tab)
- git.kernel.org/stable/c/3c6332f3bb1578b5b10ac2561247b1d6272ae937 (opens in a new tab)
- git.kernel.org/stable/c/5920ac19964f9e20181f63b410d9200ddbf8dc86 (opens in a new tab)
- git.kernel.org/stable/c/6bd23e0c2bb6c65d4f5754d1456bc9a4427fc59b (opens in a new tab)
- lists.debian.org/debian-lts-announce/2025/01/msg00001.html (opens in a new tab)