bpf: Disable preemption in bpf_event_output
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Partial Red Hat: 5 fixed, 2 without a fix
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat.
Summary
In the Linux kernel, the following vulnerability has been resolved: bpf: Disable preemption in bpf_event_output We received report [1] of kernel crash, which is caused by using nesting protection without disabled preemption. The bpf_event_output can be called by programs executed by bpf_prog_run_array_cg function that disabled migration but keeps preemption enabled. This can cause task to be preempted by another one inside the nesting protection and lead eventually to two tasks using same perf_sample_data buffer and cause crashes like: BUG: kernel NULL pointer dereference, address: 0000000000000001 #PF: supervisor instruction fetch in kernel mode #PF: error_code(0x0010) - not-present page ... ? perf_output_sample+0x12a/0x9a0 ? finish_task_switch.isra.0+0x81/0x280 ? perf_event_output+0x66/0xa0 ? bpf_event_output+0x13a/0x190 ? bpf_event_output_data+0x22/0x40 ? bpf_prog_dfc84bbde731b257_cil_sock4_connect+0x40a/0xacb ? xa_load+0x87/0xe0 ? __cgroup_bpf_run_filter_sock_addr+0xc1/0x1a0 ? release_sock+0x3e/0x90 ? sk_setsockopt+0x1a1/0x12f0 ? udp_pre_connect+0x36/0x50 ? inet_dgram_connect+0x93/0xa0 ? __sys_connect+0xb4/0xe0 ? udp_setsockopt+0x27/0x40 ? __pfx_udp_push_pending_frames+0x10/0x10 ? __sys_setsockopt+0xdf/0x1a0 ? __x64_sys_connect+0xf/0x20 ? do_syscall_64+0x3a/0x90 ? entry_SYSCALL_64_after_hwframe+0x72/0xdc Fixing this by disabling preemption in bpf_event_output. [1] https://github.com/cilium/cilium/issues/26756
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
- Fix · CNA Linux (Linux) Fixed in 5.10.190, 5.15.126, 6.1.45, 6.4.10, 6.5
Red Hat 1 advisory
- RHSA-2024:2394 Released 2024-04-30 · Red Hat rating Importantkernel security, bug fix, and enhancement update
- Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-427.13.1.el9_4, kernel-64k-debug-devel-matched-5.14.0-427.13.1.el9_4, kernel-64k-devel-5.14.0-427.13.1.el9_4 +11
- Red Hat Enterprise Linux BaseOS (v. 9) bpftool-7.3.0-427.13.1.el9_4, kernel-5.14.0-427.13.1.el9_4, kernel-64k-5.14.0-427.13.1.el9_4 +29
- Red Hat Enterprise Linux CRB (v. 9) kernel-tools-libs-devel-5.14.0-427.13.1.el9_4, libperf-5.14.0-427.13.1.el9_4
- Red Hat Enterprise Linux NFV (v. 9) kernel-rt-5.14.0-427.13.1.el9_4, kernel-rt-core-5.14.0-427.13.1.el9_4, kernel-rt-debug-5.14.0-427.13.1.el9_4 +11
- Red Hat Enterprise Linux RT (v. 9) kernel-rt-5.14.0-427.13.1.el9_4, kernel-rt-core-5.14.0-427.13.1.el9_4, kernel-rt-debug-5.14.0-427.13.1.el9_4 +9
Vendor assessments
Red Hat
Red Hat rating: Low. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 8 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 9 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux AppStream (v. 9) | Fixed | RHSA-2024:2394 |
| Red Hat Enterprise Linux BaseOS (v. 9) | Fixed | RHSA-2024:2394 |
| Red Hat Enterprise Linux CRB (v. 9) | Fixed | RHSA-2024:2394 |
| Red Hat Enterprise Linux NFV (v. 9) | Fixed | RHSA-2024:2394 |
| Red Hat Enterprise Linux RT (v. 9) | Fixed | RHSA-2024:2394 |
Not affected: 3 products
- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
Timeline
- 2026-10-02 Threatist record created from CVE-2023-54173
- 2026-10-03 Alias added: GHSA-m688-w5rr-prwm
- 2026-10-16 CISA SSVC decision points changed
References
Other 5
- https://git.kernel.org/stable/c/3048cb0dc0cc9dc74ed93690dffef00733bcad5b
- https://git.kernel.org/stable/c/c81bdf8f9f2b002d217c3d5357cdea9f2b82ff90
- https://git.kernel.org/stable/c/36dd8ca330b76585640ed32255a3c99f901e1502
- https://git.kernel.org/stable/c/063c9ce8e74e07bf94f99cd13146f42867875e8b
- https://git.kernel.org/stable/c/d62cc390c2e99ae267ffe4b8d7e2e08b6c758c32
More Linux vulnerabilities
- 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-2021-02452 Incorrect authorization in Ubuntu linux kernel 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
Sources
- CVE-2023-54173 · CVE Program
- CVE-2023-54173 · NVD
- FIRST EPSS
- GHSA-m688-w5rr-prwm · GitHub Advisory Database · CC BY 4.0
- CVE-2023-54173 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences