CVE-2026-23472: Linux kernel · Infinite Loop
Source GCVE Database
Not known to be exploited · CVSS 5.5 High · fixed in efe85a557186b7fe915572ae93a8f3f78bfd9a22 : patch Linux kernel soon.
Data as of 30 Oct 2026, 16:33 UTC
Thin evidence
One scorer or none- Patch
- Available – fixed in efe85a557186b7fe915572ae93a8f3f78bfd9a22, d45cfa70bf0159afb31cb03d2d16ec5a5053460c, c9e845014723d552944cec4e146ec7b841cda34d +3
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 3 Apr 2026
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 30 Oct 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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Description
In the Linux kernel, the following vulnerability has been resolved: serial: core: fix infinite loop in handle_tx() for PORT_UNKNOWN uart_write_room() and uart_write() behave inconsistently when xmit_buf is NULL (which happens for PORT_UNKNOWN ports that were never properly initialized): - uart_write_room() returns kfifo_avail() which can be > 0 - uart_write() checks xmit_buf and returns 0 if NULL This inconsistency causes an infinite loop in drivers that rely on tty_write_room() to determine if they can write: while (tty_write_room(tty) > 0) { written = tty->ops->write(...); // written is always 0, loop never exits } For example, caif_serial's handle_tx() enters an infinite loop when used with PORT_UNKNOWN serial ports, causing system hangs. Fix by making uart_write_room() also check xmit_buf and return 0 if it's NULL, consistent with uart_write(). Reproducer: https://gist.github.com/mrpre/d9a694cc0e19828ee3bc3b37983fde13
References
- nvd.nist.gov/vuln/detail/CVE-2026-23472 (opens in a new tab)
- git.kernel.org/stable/c/455ce986fa356ff43a43c0d363ba95fa152f21d5 (opens in a new tab)
- git.kernel.org/stable/c/91c2a5d201daf66fa3f42b8a383bb89174bde2c8 (opens in a new tab)
- git.kernel.org/stable/c/bc70f2b36cf474d5cc8ecbcaf57f3e326fdec67c (opens in a new tab)
- git.kernel.org/stable/c/c9e845014723d552944cec4e146ec7b841cda34d (opens in a new tab)
- git.kernel.org/stable/c/d45cfa70bf0159afb31cb03d2d16ec5a5053460c (opens in a new tab)
- git.kernel.org/stable/c/efe85a557186b7fe915572ae93a8f3f78bfd9a22 (opens in a new tab)