CVE-2021-47401: ipack: ipoctal: fix stack information leak

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2024-05-21 · updated 2026-08-04
Weakness: CWE-668

Description

In the Linux kernel, the following vulnerability has been resolved: ipack: ipoctal: fix stack information leak The tty driver name is used also after registering the driver and must specifically not be allocated on the stack to avoid leaking information to user space (or triggering an oops). Drivers should not try to encode topology information in the tty device name but this one snuck in through staging without anyone noticing and another driver has since copied this malpractice. Fixing the ABI is a separate issue, but this at least plugs the security hole.

Affected products

Linux kernel: from 3.5 before 4.4.286; from 4.5 before 4.9.285; from 4.10 before 4.14.249; from 4.15 before 4.19.209; from 4.20 before 5.4.151; from 5.5 before 5.10.71 — fixed in 4.14.249, 4.19.209, 4.4.286, 4.9.285, 5.10.71, 5.14.10

How to fix

Upgrade to a fixed version: Linux kernel 4.14.249, 4.19.209, 4.4.286, 4.9.285. Check the vendor advisory for mitigations.

References

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