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TI-2023-29767 Aliases CVE-2023-53478GHSA-q32w-2qjp-8m8q

tracing/synthetic: Fix races on freeing last_cmd

Priority LOW 33CWE-362Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA.

Summary

In the Linux kernel, the following vulnerability has been resolved: tracing/synthetic: Fix races on freeing last_cmd Currently, the "last_cmd" variable can be accessed by multiple processes asynchronously when multiple users manipulate synthetic_events node at the same time, it could lead to use-after-free or double-free. This patch add "lastcmd_mutex" to prevent "last_cmd" from being accessed asynchronously. ================================================================ It's easy to reproduce in the KASAN environment by running the two scripts below in different shells. script 1: while : do echo -n -e '\x88' > /sys/kernel/tracing/synthetic_events done script 2: while : do echo -n -e '\xb0' > /sys/kernel/tracing/synthetic_events done ================================================================ double-free scenario: process A process B ------------------- --------------- 1.kstrdup last_cmd 2.free last_cmd 3.free last_cmd(double-free) ================================================================ use-after-free scenario: process A process B ------------------- --------------- 1.kstrdup last_cmd 2.free last_cmd 3.tracing_log_err(use-after-free) ================================================================ Appendix 1. KASAN report double-free: BUG: KASAN: double-free in kfree+0xdc/0x1d4 Free of addr ***** by task sh/4879 Call trace: ... kfree+0xdc/0x1d4 create_or_delete_synth_event+0x60/0x1e8 trace_parse_run_command+0x2bc/0x4b8 synth_events_write+0x20/0x30 vfs_write+0x200/0x830 ... Allocated by task 4879: ... kstrdup+0x5c/0x98 create_or_delete_synth_event+0x6c/0x1e8 trace_parse_run_command+0x2bc/0x4b8 synth_events_write+0x20/0x30 vfs_write+0x200/0x830 ... Freed by task 5464: ... kfree+0xdc/0x1d4 create_or_delete_synth_event+0x60/0x1e8 trace_parse_run_command+0x2bc/0x4b8 synth_events_write+0x20/0x30 vfs_write+0x200/0x830 ... ================================================================ Appendix 2. KASAN report use-after-free: BUG: KASAN: use-after-free in strlen+0x5c/0x7c Read of size 1 at addr ***** by task sh/5483 sh: CPU: 7 PID: 5483 Comm: sh ... __asan_report_load1_noabort+0x34/0x44 strlen+0x5c/0x7c tracing_log_err+0x60/0x444 create_or_delete_synth_event+0xc4/0x204 trace_parse_run_command+0x2bc/0x4b8 synth_events_write+0x20/0x30 vfs_write+0x200/0x830 ... Allocated by task 5483: ... kstrdup+0x5c/0x98 create_or_delete_synth_event+0x80/0x204 trace_parse_run_command+0x2bc/0x4b8 synth_events_write+0x20/0x30 vfs_write+0x200/0x830 ... Freed by task 5480: ... kfree+0xdc/0x1d4 create_or_delete_synth_event+0x74/0x204 trace_parse_run_command+0x2bc/0x4b8 synth_events_write+0x20/0x30 vfs_write+0x200/0x830 ...

Why it matters now

EPSS 0.00116 1st percentileScored 2026-11-07
Fix Fixed Linux (Linux): 6.1.24, 6.2.11, 6.3

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux5.18 and later6.1.24, 6.2.11, 6.3Patch availableCNA
  • Linux VendorLinux Affected 5.18 and later Fixed in 6.1.24, 6.2.11, 6.3 Patch available CNA

CPE configurations NVD · 6

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*5.18 to before 6.1.24; 6.2 to before 6.2.11VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.3:rc1:*:*:*:*:*:*6.3 rc1VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.3:rc2:*:*:*:*:*:*6.3 rc2VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.3:rc3:*:*:*:*:*:*6.3 rc3VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.3:rc4:*:*:*:*:*:*6.3 rc4VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.3:rc5:*:*:*:*:*:*6.3 rc5VulnerableLinux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 5.18 to before 6.1.24; 6.2 to before 6.2.11 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.3:rc1:*:*:*:*:*:* Versions 6.3 rc1 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.3:rc2:*:*:*:*:*:* Versions 6.3 rc2 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.3:rc3:*:*:*:*:*:* Versions 6.3 rc3 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.3:rc4:*:*:*:*:*:* Versions 6.3 rc4 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.3:rc5:*:*:*:*:*:* Versions 6.3 rc5 Vulnerable ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 6.1.24, 6.2.11, 6.3

Vendor assessments

Red Hat

Red Hat rating: Low. Red Hat's page for this CVE →

Not affected: 5 products
  • Red Hat Enterprise Linux 10
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8
  • Red Hat Enterprise Linux 9

Timeline

  1. 2026-10-02 Threatist record created from CVE-2023-53478
  2. 2026-10-03 Alias added: GHSA-q32w-2qjp-8m8q
  3. 2026-11-07 Affected versions changed · Red Hat

References

Patch 3

  • TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
  • TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
  • TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
  • TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
  • TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
See all 15278 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences