CVE-2021-47356

mISDN: fix possible use-after-free in HFC_cleanup()

State: Published
Severity: 7.7 High
Published: May 21, 2024
Updated: May 11, 2026
Reserved: May 21, 2024

Description

In the Linux kernel, the following vulnerability has been resolved:

mISDN: fix possible use-after-free in HFC_cleanup()

This module's remove path calls del_timer(). However, that function does not wait until the timer handler finishes. This means that the timer handler may still be running after the driver's remove function has finished, which would result in a use-after-free.

Fix by calling del_timer_sync(), which makes sure the timer handler has finished, and unable to re-schedule itself.

Scores

CVSS	Score	Vector	Source
3.1	7.7 High	CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H	CISA-ADP

Weaknesses

CWE-416 Use After Free

Affected Products

Product	Versions
LinuxLinux	87c5fa1bb42624254a2013cbbc3b170d6017f5d6 to before 49331c07ef0f8fdfa42b30ba6a83a657b29d7fbeAffected 87c5fa1bb42624254a2013cbbc3b170d6017f5d6 to before 54ff3202928952a100c477248e65ac6db01258a7Affected 87c5fa1bb42624254a2013cbbc3b170d6017f5d6 to before 7867ddc5f3de7f289aee63233afc0df4b62834c5Affected 87c5fa1bb42624254a2013cbbc3b170d6017f5d6 to before 5f2818185da0fe82a932f0856633038b66faf124Affected 87c5fa1bb42624254a2013cbbc3b170d6017f5d6 to before 3ecd228c636ee17c14662729737fa07242a93cb0Affected 87c5fa1bb42624254a2013cbbc3b170d6017f5d6 to before b7ee9ae1e0cf55a037c4a99af2acc5d78cb7802dAffected 87c5fa1bb42624254a2013cbbc3b170d6017f5d6 to before 61370ff07e0acc657559a8fac02551dfeb9d3020Affected 87c5fa1bb42624254a2013cbbc3b170d6017f5d6 to before ed7c3739d0a07e2ec3ccbffe7e93cea01c438cdaAffected 87c5fa1bb42624254a2013cbbc3b170d6017f5d6 to before 009fc857c5f6fda81f2f7dd851b2d54193a8e733Affected
LinuxLinux	2.6.29Affected before 2.6.29Not affected 4.4.276 through 4.4.Not affected 4.9.276 through 4.9.Not affected 4.14.240 through 4.14.Not affected 4.19.198 through 4.19.Not affected 5.4.133 through 5.4.Not affected 5.10.51 through 5.10.Not affected 5.12.18 through 5.12.Not affected 5.13.3 through 5.13.Not affected 5.14 and laterNot affected

Product

Versions

LinuxLinux

87c5fa1bb42624254a2013cbbc3b170d6017f5d6 to before 49331c07ef0f8fdfa42b30ba6a83a657b29d7fbeAffected
87c5fa1bb42624254a2013cbbc3b170d6017f5d6 to before 54ff3202928952a100c477248e65ac6db01258a7Affected
87c5fa1bb42624254a2013cbbc3b170d6017f5d6 to before 7867ddc5f3de7f289aee63233afc0df4b62834c5Affected
87c5fa1bb42624254a2013cbbc3b170d6017f5d6 to before 5f2818185da0fe82a932f0856633038b66faf124Affected
87c5fa1bb42624254a2013cbbc3b170d6017f5d6 to before 3ecd228c636ee17c14662729737fa07242a93cb0Affected
87c5fa1bb42624254a2013cbbc3b170d6017f5d6 to before b7ee9ae1e0cf55a037c4a99af2acc5d78cb7802dAffected
87c5fa1bb42624254a2013cbbc3b170d6017f5d6 to before 61370ff07e0acc657559a8fac02551dfeb9d3020Affected
87c5fa1bb42624254a2013cbbc3b170d6017f5d6 to before ed7c3739d0a07e2ec3ccbffe7e93cea01c438cdaAffected
87c5fa1bb42624254a2013cbbc3b170d6017f5d6 to before 009fc857c5f6fda81f2f7dd851b2d54193a8e733Affected

LinuxLinux

2.6.29Affected
before 2.6.29Not affected
4.4.276 through 4.4.*Not affected
4.9.276 through 4.9.*Not affected
4.14.240 through 4.14.*Not affected
4.19.198 through 4.19.*Not affected
5.4.133 through 5.4.*Not affected
5.10.51 through 5.10.*Not affected
5.12.18 through 5.12.*Not affected
5.13.3 through 5.13.*Not affected
5.14 and laterNot affected

References

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