CVE-2026-90336: Linux kernel · serial: core: clear freed pointers on uart_register_driver() failure
Source GCVE Database
Not known to be exploited · fixed in ddf51d74ee9f9857c99477329d80408cedebda61 : update Linux kernel when convenient.
Data as of 30 Oct 2026, 18:21 UTC
Rated Medium by Threat Radar's AI analysis · CVSS not yet scored by NVD
Thin evidence
One scorer or none- Patch
- Available – fixed in ddf51d74ee9f9857c99477329d80408cedebda61, a9c0ffe5930c97b352f32febfc59a6e6ae6772ee, 802e2192a9d38027730c2869c67c9131b8c8fe9f +3
Exploitation evidence
Disclosed: evidence found.
CVE published 17 Sep 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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AI-suggested
A fix has been implemented that clears the freed pointers on failure paths in uart_register_driver(). Users should apply the official Linux kernel updates that include this fix. Since this is a kernel-level issue, updating to a patched kernel version is the recommended remediation.
Description
A vulnerability in the Linux kernel's serial core was resolved involving improper clearing of freed pointers on uart_register_driver() failure. Specifically, when tty_alloc_driver() or tty_register_driver() fail, pointers drv->state and drv->tty_driver may still reference freed memory. This can cause drivers to mistakenly skip registration and pass invalid pointers to uart_add_one_port(). The issue was identified using failslab on QEMU's raspi1ap board and fixed by clearing these pointers on failure paths.
References
- nvd.nist.gov/vuln/detail/CVE-2026-90336 (opens in a new tab)
- git.kernel.org/stable/c/06b376432974fe5f25f2843a8e8438c6a1cf3d50 (opens in a new tab)
- git.kernel.org/stable/c/5e260edd28eddc3b92c9f578df3026fd11c710cf (opens in a new tab)
- git.kernel.org/stable/c/61a2fb25551be0375bc16ef2a70c987dfca26183 (opens in a new tab)
- git.kernel.org/stable/c/802e2192a9d38027730c2869c67c9131b8c8fe9f (opens in a new tab)
- git.kernel.org/stable/c/a9c0ffe5930c97b352f32febfc59a6e6ae6772ee (opens in a new tab)
- git.kernel.org/stable/c/ddf51d74ee9f9857c99477329d80408cedebda61 (opens in a new tab)