CVE-2026-93050
Received
Received - Intake
BaseFortify
Vulnerability report for CVE-2026-93050, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-09-17
Last updated on: 2026-09-17
Assigner: kernel.org
Description
Description
In the Linux kernel, the following vulnerability has been resolved:
ipack: ipoctal: fix UAF, null-ptr-deref, and use-after-free in cleanup on remove
Three issues arise when the device is removed while a tty session is
still active:
1. UAF of struct ipoctal: the remove callback frees ipoctal via
kfree() while tty ops may still access it. Fix by introducing
kref-based lifetime management — kref is taken in install() when
a tty is opened and released in cleanup() when the tty is finally
destroyed; remove() uses kref_put() instead of kfree().
2. NULL dereference in ipoctal_write_tty(): __ipoctal_remove()
frees xmit_buf via tty_port_free_xmit_buf() while a userspace
process may still hold the tty fd and call write(). Fix by
checking for NULL xmit_buf in ipoctal_write_tty().
3. UAF in ipoctal_cleanup(): ipack_put_carrier(ipoctal->dev)
dereferences ipoctal->dev after the ipack_device has been freed
by ipack_device_del(). Fix by caching ipoctal->carrier_owner
during probe() and calling module_put() on the cached pointer
directly in cleanup(), avoiding any access to ipoctal->dev.
Also introduce a "removed" flag in struct ipoctal, set at the start
of __ipoctal_remove(), and checked in every tty op that accesses
hardware resources (port_activate, write_tty, set_termios, hangup,
shutdown). This prevents page faults when devm_ioremap() regions
are unmapped after remove() returns.
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
Currently, no data is known.
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-UNKNOWN |
