CyberSecBulletin
CVE-2024-46746NVD status: Modified

Linux: Use After Free

Published Updated By the CyberSecBulletin desk

CVE-2024-46746 is a high-severity use after free vulnerability in Linux, with a CVSS 3.1 base score of 7.8 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. The record lists versions 86b4f5cf91ca03c08e3822ac89476a677a780bcc, 775125c7fe38533aaa4b20769f5b5e62cc1170a0, 60dc4ee0428d70bcbb41436b6729d29f1cbdfb89 as the first without the flaw, so updating Linux to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.25% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Linux to 86b4f5cf91ca03c08e3822ac89476a677a780bcc or 775125c7fe38533aaa4b20769f5b5e62cc1170a0 or 60dc4ee0428d70bcbb41436b6729d29f1cbdfb89 or adb3e3c1ddb5a23b8b7122ef1913f528d728937c, whichever matches your release line, or a later version.
  2. Update Linux Kernel to 5.15.167 or 6.1.110 or 6.6.51 or 6.10.10, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinux4f567b9f8141a86c7d878fadf136e5d1408e3e61 up to, but not including, 86b4f5cf91ca03c08e3822ac89476a677a780bcc; 4f567b9f8141a86c7d878fadf136e5d1408e3e61 up to, but not including, 775125c7fe38533aaa4b20769f5b5e62cc1170a0; 4f567b9f8141a86c7d878fadf136e5d1408e3e61 up to, but not including, 60dc4ee0428d70bcbb41436b6729d29f1cbdfb89; 4f567b9f8141a86c7d878fadf136e5d1408e3e61 up to, but not including, adb3e3c1ddb5a23b8b7122ef1913f528d728937c; 4f567b9f8141a86c7d878fadf136e5d1408e3e61 up to, but not including, 97155021ae17b86985121b33cf8098bcde00d497; 5.1186b4f5cf91ca03c08e3822ac89476a677a780bcc, 775125c7fe38533aaa4b20769f5b5e62cc1170a0, 60dc4ee0428d70bcbb41436b6729d29f1cbdfb89, adb3e3c1ddb5a23b8b7122ef1913f528d728937c, 97155021ae17b86985121b33cf8098bcde00d497
DebianDebian Linux11.0Not stated
LinuxLinux Kernel5.11 up to, but not including, 5.15.167; 5.16 up to, but not including, 6.1.110; 6.2 up to, but not including, 6.6.51; 6.7 up to, but not including, 6.10.10; 6.115.15.167, 6.1.110, 6.6.51, 6.10.10

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
LocalThe attacker needs local access or must trick a user into running something.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.17.8HighCNA
CVSS 3.17.8HighNVD

Official description

In the Linux kernel, the following vulnerability has been resolved: HID: amd_sfh: free driver_data after destroying hid device HID driver callbacks aren't called anymore once hid_destroy_device() has been called. Hence, hid driver_data should be freed only after the hid_destroy_device() function returned as driver_data is used in several callbacks. I observed a crash with kernel 6.10.0 on my T14s Gen 3, after enabling KASAN to debug memory allocation, I got this output: [ 13.050438] ================================================================== [ 13.054060] BUG: KASAN: slab-use-after-free in amd_sfh_get_report+0x3ec/0x530 [amd_sfh] [ 13.054809] psmouse serio1: trackpoint: Synaptics TrackPoint firmware: 0x02, buttons: 3/3 [ 13.056432] Read of size 8 at addr ffff88813152f408 by task (udev-worker)/479 [ 13.060970] CPU: 5 PID: 479 Comm: (udev-worker) Not tainted 6.10.0-arch1-2 #1 893bb55d7f0073f25c46adbb49eb3785fefd74b0 [ 13.063978] Hardware name: LENOVO 21CQCTO1WW/21CQCTO1WW, BIOS R22ET70W (1.40 ) 03/21/2024 [ 13.067860] Call Trace: [ 13.069383] input: TPPS/2 Synaptics TrackPoint as /devices/platform/i8042/serio1/input/input8 [ 13.071486] <TASK> [ 13.071492] dump_stack_lvl+0x5d/0x80 [ 13.074870] snd_hda_intel 0000:33:00.6: enabling device (0000 -> 0002) [ 13.078296] ? amd_sfh_get_report+0x3ec/0x530 [amd_sfh 05f43221435b5205f734cd9da29399130f398a38] [ 13.082199] print_report+0x174/0x505 [ 13.085776] ? __pfx__raw_spin_lock_irqsave+0x10/0x10 [ 13.089367] ? srso_alias_return_thunk+0x5/0xfbef5 [ 13.093255] ? amd_sfh_get_report+0x3ec/0x530 [amd_sfh 05f43221435b5205f734cd9da29399130f398a38] [ 13.097464] kasan_report+0xc8/0x150 [ 13.101461] ? amd_sfh_get_report+0x3ec/0x530 [amd_sfh 05f43221435b5205f734cd9da29399130f398a38] [ 13.105802] amd_sfh_get_report+0x3ec/0x530 [amd_sfh 05f43221435b5205f734cd9da29399130f398a38] [ 13.110303] amdtp_hid_request+0xb8/0x110 [amd_sfh 05f43221435b5205f734cd9da29399130f398a38] [ 13.114879] ? srso_alias_return_thunk+0x5/0xfbef5 [ 13.119450] sensor_hub_get_feature+0x1d3/0x540 [hid_sensor_hub 3f13be3016ff415bea03008d45d99da837ee3082] [ 13.124097] hid_sensor_parse_common_attributes+0x4d0/0xad0 [hid_sensor_iio_common c3a5cbe93969c28b122609768bbe23efe52eb8f5] [ 13.127404] ? srso_alias_return_thunk+0x5/0xfbef5 [ 13.131925] ? __pfx_hid_sensor_parse_common_attributes+0x10/0x10 [hid_sensor_iio_common c3a5cbe93969c28b122609768bbe23efe52eb8f5] [ 13.136455] ? _raw_spin_lock_irqsave+0x96/0xf0 [ 13.140197] ? __pfx__raw_spin_lock_irqsave+0x10/0x10 [ 13.143602] ? devm_iio_device_alloc+0x34/0x50 [industrialio 3d261d5e5765625d2b052be40e526d62b1d2123b] [ 13.147234] ? srso_alias_return_thunk+0x5/0xfbef5 [ 13.150446] ? __devm_add_action+0x167/0x1d0 [ 13.155061] hid_gyro_3d_probe+0x120/0x7f0 [hid_sensor_gyro_3d 63da36a143b775846ab2dbb86c343b401b5e3172] [ 13.158581] ? srso_alias_return_thunk+0x5/0xfbef5 [ 13.161814] platform_probe+0xa2/0x150 [ 13.165029] really_probe+0x1e3/0x8a0 [ 13.168243] __driver_probe_device+0x18c/0x370 [ 13.171500] driver_probe_device+0x4a/0x120 [ 13.175000] __driver_attach+0x190/0x4a0 [ 13.178521] ? __pfx___driver_attach+0x10/0x10 [ 13.181771] bus_for_each_dev+0x106/0x180 [ 13.185033] ? __pfx__raw_spin_lock+0x10/0x10 [ 13.188229] ? __pfx_bus_for_each_dev+0x10/0x10 [ 13.191446] ? srso_alias_return_thunk+0x5/0xfbef5 [ 13.194382] bus_add_driver+0x29e/0x4d0 [ 13.197328] driver_register+0x1a5/0x360 [ 13.200283] ? __pfx_hid_gyro_3d_platform_driver_init+0x10/0x10 [hid_sensor_gyro_3d 63da36a143b775846ab2dbb86c343b401b5e3172] [ 13.203362] do_one_initcall+0xa7/0x380 [ 13.206432] ? __pfx_do_one_initcall+0x10/0x10 [ 13.210175] ? srso_alias_return_thunk+0x5/0xfbef5 [ 13.213211] ? kasan_unpoison+0x44/0x70 [ 13.216688] do_init_module+0x238/0x750 [ 13.2196 ---truncated---

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Use After Free

The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.

How developers prevent this class of flaw

  • Choose a language that provides automatic memory management.
  • When freeing pointers, be sure to set them to NULL once they are freed. However, the utilization of multiple or complex data structures may lower the usefulness of this strategy.

More Use After Free vulnerabilities (CWE-416)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Recent Use After Free vulnerabilities

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