5.5
MEDIUM CVSS 3.1
CVE-2023-52856
Linux Lontium LT8912B Dangling Pointer Vulnerability
Description

In the Linux kernel, the following vulnerability has been resolved: drm/bridge: lt8912b: Fix crash on bridge detach The lt8912b driver, in its bridge detach function, calls drm_connector_unregister() and drm_connector_cleanup(). drm_connector_unregister() should be called only for connectors explicitly registered with drm_connector_register(), which is not the case in lt8912b. The driver's drm_connector_funcs.destroy hook is set to drm_connector_cleanup(). Thus the driver should not call either drm_connector_unregister() nor drm_connector_cleanup() in its lt8912_bridge_detach(), as they cause a crash on bridge detach: Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 Mem abort info: ESR = 0x0000000096000006 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 FSC = 0x06: level 2 translation fault Data abort info: ISV = 0, ISS = 0x00000006, ISS2 = 0x00000000 CM = 0, WnR = 0, TnD = 0, TagAccess = 0 GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 user pgtable: 4k pages, 48-bit VAs, pgdp=00000000858f3000 [0000000000000000] pgd=0800000085918003, p4d=0800000085918003, pud=0800000085431003, pmd=0000000000000000 Internal error: Oops: 0000000096000006 [#1] PREEMPT SMP Modules linked in: tidss(-) display_connector lontium_lt8912b tc358768 panel_lvds panel_simple drm_dma_helper drm_kms_helper drm drm_panel_orientation_quirks CPU: 3 PID: 462 Comm: rmmod Tainted: G W 6.5.0-rc2+ #2 Hardware name: Toradex Verdin AM62 on Verdin Development Board (DT) pstate: 80000005 (Nzcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : drm_connector_cleanup+0x78/0x2d4 [drm] lr : lt8912_bridge_detach+0x54/0x6c [lontium_lt8912b] sp : ffff800082ed3a90 x29: ffff800082ed3a90 x28: ffff0000040c1940 x27: 0000000000000000 x26: 0000000000000000 x25: dead000000000122 x24: dead000000000122 x23: dead000000000100 x22: ffff000003fb6388 x21: 0000000000000000 x20: 0000000000000000 x19: ffff000003fb6260 x18: fffffffffffe56e8 x17: 0000000000000000 x16: 0010000000000000 x15: 0000000000000038 x14: 0000000000000000 x13: ffff800081914b48 x12: 000000000000040e x11: 000000000000015a x10: ffff80008196ebb8 x9 : ffff800081914b48 x8 : 00000000ffffefff x7 : ffff0000040c1940 x6 : ffff80007aa649d0 x5 : 0000000000000000 x4 : 0000000000000001 x3 : ffff80008159e008 x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000 Call trace: drm_connector_cleanup+0x78/0x2d4 [drm] lt8912_bridge_detach+0x54/0x6c [lontium_lt8912b] drm_bridge_detach+0x44/0x84 [drm] drm_encoder_cleanup+0x40/0xb8 [drm] drmm_encoder_alloc_release+0x1c/0x30 [drm] drm_managed_release+0xac/0x148 [drm] drm_dev_put.part.0+0x88/0xb8 [drm] devm_drm_dev_init_release+0x14/0x24 [drm] devm_action_release+0x14/0x20 release_nodes+0x5c/0x90 devres_release_all+0x8c/0xe0 device_unbind_cleanup+0x18/0x68 device_release_driver_internal+0x208/0x23c driver_detach+0x4c/0x94 bus_remove_driver+0x70/0xf4 driver_unregister+0x30/0x60 platform_driver_unregister+0x14/0x20 tidss_platform_driver_exit+0x18/0xb2c [tidss] __arm64_sys_delete_module+0x1a0/0x2b4 invoke_syscall+0x48/0x110 el0_svc_common.constprop.0+0x60/0x10c do_el0_svc_compat+0x1c/0x40 el0_svc_compat+0x40/0xac el0t_32_sync_handler+0xb0/0x138 el0t_32_sync+0x194/0x198 Code: 9104a276 f2fbd5b7 aa0203e1 91008af8 (f85c0420)

INFO

Published Date :

May 21, 2024, 4:15 p.m.

Last Modified :

Jan. 31, 2025, 4:01 p.m.

Remotely Exploit :

No

Source :

416baaa9-dc9f-4396-8d5f-8c081fb06d67
Affected Products

The following products are affected by CVE-2023-52856 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Linux linux_kernel
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 MEDIUM [email protected]
Solution
This vulnerability is fixed by updating the Linux kernel to a patched version.
  • Update the affected Linux kernel packages.
  • Reboot the system to apply the update.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2023-52856 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2023-52856 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2023-52856 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2023-52856 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • Initial Analysis by [email protected]

    Jan. 31, 2025

    Action Type Old Value New Value
    Added CVSS V3.1 NIST AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
    Added CWE NIST CWE-476
    Added CPE Configuration OR *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.13 up to (excluding) 5.15.139 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.16 up to (excluding) 6.1.63 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.2 up to (excluding) 6.5.12 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.6 up to (excluding) 6.6.2
    Changed Reference Type https://git.kernel.org/stable/c/42071feab712ba2a139b8928f7e0f8d3a6fc719e No Types Assigned https://git.kernel.org/stable/c/42071feab712ba2a139b8928f7e0f8d3a6fc719e Patch
    Changed Reference Type https://git.kernel.org/stable/c/42071feab712ba2a139b8928f7e0f8d3a6fc719e No Types Assigned https://git.kernel.org/stable/c/42071feab712ba2a139b8928f7e0f8d3a6fc719e Patch
    Changed Reference Type https://git.kernel.org/stable/c/44283993144a03af9df31934d6c32bbd42d1a347 No Types Assigned https://git.kernel.org/stable/c/44283993144a03af9df31934d6c32bbd42d1a347 Patch
    Changed Reference Type https://git.kernel.org/stable/c/44283993144a03af9df31934d6c32bbd42d1a347 No Types Assigned https://git.kernel.org/stable/c/44283993144a03af9df31934d6c32bbd42d1a347 Patch
    Changed Reference Type https://git.kernel.org/stable/c/7bf0cb8f40280a85034990dfe42be8ca8f80f37a No Types Assigned https://git.kernel.org/stable/c/7bf0cb8f40280a85034990dfe42be8ca8f80f37a Patch
    Changed Reference Type https://git.kernel.org/stable/c/7bf0cb8f40280a85034990dfe42be8ca8f80f37a No Types Assigned https://git.kernel.org/stable/c/7bf0cb8f40280a85034990dfe42be8ca8f80f37a Patch
    Changed Reference Type https://git.kernel.org/stable/c/b65e3249f3ca96e3c736af889461d80d675feab6 No Types Assigned https://git.kernel.org/stable/c/b65e3249f3ca96e3c736af889461d80d675feab6 Patch
    Changed Reference Type https://git.kernel.org/stable/c/b65e3249f3ca96e3c736af889461d80d675feab6 No Types Assigned https://git.kernel.org/stable/c/b65e3249f3ca96e3c736af889461d80d675feab6 Patch
    Changed Reference Type https://git.kernel.org/stable/c/fcd9895e365474709844eeb31cfe53d912c3596e No Types Assigned https://git.kernel.org/stable/c/fcd9895e365474709844eeb31cfe53d912c3596e Patch
    Changed Reference Type https://git.kernel.org/stable/c/fcd9895e365474709844eeb31cfe53d912c3596e No Types Assigned https://git.kernel.org/stable/c/fcd9895e365474709844eeb31cfe53d912c3596e Patch
  • CVE Modified by af854a3a-2127-422b-91ae-364da2661108

    Nov. 21, 2024

    Action Type Old Value New Value
    Added Reference https://git.kernel.org/stable/c/42071feab712ba2a139b8928f7e0f8d3a6fc719e
    Added Reference https://git.kernel.org/stable/c/44283993144a03af9df31934d6c32bbd42d1a347
    Added Reference https://git.kernel.org/stable/c/7bf0cb8f40280a85034990dfe42be8ca8f80f37a
    Added Reference https://git.kernel.org/stable/c/b65e3249f3ca96e3c736af889461d80d675feab6
    Added Reference https://git.kernel.org/stable/c/fcd9895e365474709844eeb31cfe53d912c3596e
  • CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    May. 29, 2024

    Action Type Old Value New Value
  • CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    May. 21, 2024

    Action Type Old Value New Value
    Added Description In the Linux kernel, the following vulnerability has been resolved: drm/bridge: lt8912b: Fix crash on bridge detach The lt8912b driver, in its bridge detach function, calls drm_connector_unregister() and drm_connector_cleanup(). drm_connector_unregister() should be called only for connectors explicitly registered with drm_connector_register(), which is not the case in lt8912b. The driver's drm_connector_funcs.destroy hook is set to drm_connector_cleanup(). Thus the driver should not call either drm_connector_unregister() nor drm_connector_cleanup() in its lt8912_bridge_detach(), as they cause a crash on bridge detach: Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 Mem abort info: ESR = 0x0000000096000006 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 FSC = 0x06: level 2 translation fault Data abort info: ISV = 0, ISS = 0x00000006, ISS2 = 0x00000000 CM = 0, WnR = 0, TnD = 0, TagAccess = 0 GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 user pgtable: 4k pages, 48-bit VAs, pgdp=00000000858f3000 [0000000000000000] pgd=0800000085918003, p4d=0800000085918003, pud=0800000085431003, pmd=0000000000000000 Internal error: Oops: 0000000096000006 [#1] PREEMPT SMP Modules linked in: tidss(-) display_connector lontium_lt8912b tc358768 panel_lvds panel_simple drm_dma_helper drm_kms_helper drm drm_panel_orientation_quirks CPU: 3 PID: 462 Comm: rmmod Tainted: G W 6.5.0-rc2+ #2 Hardware name: Toradex Verdin AM62 on Verdin Development Board (DT) pstate: 80000005 (Nzcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : drm_connector_cleanup+0x78/0x2d4 [drm] lr : lt8912_bridge_detach+0x54/0x6c [lontium_lt8912b] sp : ffff800082ed3a90 x29: ffff800082ed3a90 x28: ffff0000040c1940 x27: 0000000000000000 x26: 0000000000000000 x25: dead000000000122 x24: dead000000000122 x23: dead000000000100 x22: ffff000003fb6388 x21: 0000000000000000 x20: 0000000000000000 x19: ffff000003fb6260 x18: fffffffffffe56e8 x17: 0000000000000000 x16: 0010000000000000 x15: 0000000000000038 x14: 0000000000000000 x13: ffff800081914b48 x12: 000000000000040e x11: 000000000000015a x10: ffff80008196ebb8 x9 : ffff800081914b48 x8 : 00000000ffffefff x7 : ffff0000040c1940 x6 : ffff80007aa649d0 x5 : 0000000000000000 x4 : 0000000000000001 x3 : ffff80008159e008 x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000 Call trace: drm_connector_cleanup+0x78/0x2d4 [drm] lt8912_bridge_detach+0x54/0x6c [lontium_lt8912b] drm_bridge_detach+0x44/0x84 [drm] drm_encoder_cleanup+0x40/0xb8 [drm] drmm_encoder_alloc_release+0x1c/0x30 [drm] drm_managed_release+0xac/0x148 [drm] drm_dev_put.part.0+0x88/0xb8 [drm] devm_drm_dev_init_release+0x14/0x24 [drm] devm_action_release+0x14/0x20 release_nodes+0x5c/0x90 devres_release_all+0x8c/0xe0 device_unbind_cleanup+0x18/0x68 device_release_driver_internal+0x208/0x23c driver_detach+0x4c/0x94 bus_remove_driver+0x70/0xf4 driver_unregister+0x30/0x60 platform_driver_unregister+0x14/0x20 tidss_platform_driver_exit+0x18/0xb2c [tidss] __arm64_sys_delete_module+0x1a0/0x2b4 invoke_syscall+0x48/0x110 el0_svc_common.constprop.0+0x60/0x10c do_el0_svc_compat+0x1c/0x40 el0_svc_compat+0x40/0xac el0t_32_sync_handler+0xb0/0x138 el0t_32_sync+0x194/0x198 Code: 9104a276 f2fbd5b7 aa0203e1 91008af8 (f85c0420)
    Added Reference kernel.org https://git.kernel.org/stable/c/42071feab712ba2a139b8928f7e0f8d3a6fc719e [No types assigned]
    Added Reference kernel.org https://git.kernel.org/stable/c/7bf0cb8f40280a85034990dfe42be8ca8f80f37a [No types assigned]
    Added Reference kernel.org https://git.kernel.org/stable/c/fcd9895e365474709844eeb31cfe53d912c3596e [No types assigned]
    Added Reference kernel.org https://git.kernel.org/stable/c/b65e3249f3ca96e3c736af889461d80d675feab6 [No types assigned]
    Added Reference kernel.org https://git.kernel.org/stable/c/44283993144a03af9df31934d6c32bbd42d1a347 [No types assigned]
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
Vulnerability Scoring Details
Base CVSS Score: 5.5
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality Impact
Integrity Impact
Availability Impact