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TI-2024-17613 Aliases CVE-2024-26737GHSA-8x8h-8p2w-8g4f

bpf: Fix racing between bpf_timer_cancel_and_free and bpf_timer_cancel

Priority LOW 34CWE-416Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 10 fixed, 2 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-416 and the CVSS impact.

Summary

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix racing between bpf_timer_cancel_and_free and bpf_timer_cancel The following race is possible between bpf_timer_cancel_and_free and bpf_timer_cancel. It will lead a UAF on the timer->timer. bpf_timer_cancel(); spin_lock(); t = timer->time; spin_unlock(); bpf_timer_cancel_and_free(); spin_lock(); t = timer->timer; timer->timer = NULL; spin_unlock(); hrtimer_cancel(&t->timer); kfree(t); /* UAF on t */ hrtimer_cancel(&t->timer); In bpf_timer_cancel_and_free, this patch frees the timer->timer after a rcu grace period. This requires a rcu_head addition to the "struct bpf_hrtimer". Another kfree(t) happens in bpf_timer_init, this does not need a kfree_rcu because it is still under the spin_lock and timer->timer has not been visible by others yet. In bpf_timer_cancel, rcu_read_lock() is added because this helper can be used in a non rcu critical section context (e.g. from a sleepable bpf prog). Other timer->timer usages in helpers.c have been audited, bpf_timer_cancel() is the only place where timer->timer is used outside of the spin_lock. Another solution considered is to mark a t->flag in bpf_timer_cancel and clear it after hrtimer_cancel() is done. In bpf_timer_cancel_and_free, it busy waits for the flag to be cleared before kfree(t). This patch goes with a straight forward solution and frees timer->timer after a rcu grace period.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00253 16th percentileScored 2026-11-07
Fix Partial Linux (Linux): 5.15.150, 6.1.80, 6.6.19 +2Red Hat: 3 advisoriesRed Hat: 10 fixed, 2 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux5.15 and later5.15.150, 6.1.80, 6.6.19, 6.7.7, 6.8Patch availableCNA
  • Linux VendorLinux Affected 5.15 and later Fixed in 5.15.150, 6.1.80, 6.6.19, 6.7.7, 6.8 Patch available CNA

CPE configurations NVD · 6

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*5.15 to before 5.15.150; 5.16 to before 6.1.80; 6.2 to before 6.6.19; 6.7 to before 6.7.7VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.8:rc1:*:*:*:*:*:*6.8 rc1VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.8:rc2:*:*:*:*:*:*6.8 rc2VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.8:rc3:*:*:*:*:*:*6.8 rc3VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.8:rc4:*:*:*:*:*:*6.8 rc4VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.8:rc5:*:*:*:*:*:*6.8 rc5VulnerableLinux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 5.15 to before 5.15.150; 5.16 to before 6.1.80; 6.2 to before 6.6.19; 6.7 to before 6.7.7 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.8:rc1:*:*:*:*:*:* Versions 6.8 rc1 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.8:rc2:*:*:*:*:*:* Versions 6.8 rc2 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.8:rc3:*:*:*:*:*:* Versions 6.8 rc3 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.8:rc4:*:*:*:*:*:* Versions 6.8 rc4 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.8:rc5:*:*:*:*:*:* Versions 6.8 rc5 Vulnerable ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 5.15.150, 6.1.80, 6.6.19, 6.7.7, 6.8

Red Hat 3 advisories

  • RHSA-2024:5066 Released 2024-08-07 · Red Hat rating Moderate
    kernel security update
    • Red Hat CodeReady Linux Builder EUS (v.9.2) kernel-tools-libs-devel-5.14.0-284.77.1.el9_2
    • Red Hat Enterprise Linux AppStream EUS (v.9.2) kernel-64k-debug-devel-5.14.0-284.77.1.el9_2, kernel-64k-debug-devel-matched-5.14.0-284.77.1.el9_2, kernel-64k-devel-5.14.0-284.77.1.el9_2 +9
    • Red Hat Enterprise Linux BaseOS EUS (v.9.2) bpftool-7.0.0-284.77.1.el9_2, kernel-5.14.0-284.77.1.el9_2, kernel-64k-5.14.0-284.77.1.el9_2 +29
  • RHSA-2024:5067 Released 2024-08-07 · Red Hat rating Moderate
    kernel-rt security update
    • Red Hat Enterprise Linux Real Time EUS (v.9.2) kernel-rt-5.14.0-284.77.1.rt14.362.el9_2, kernel-rt-core-5.14.0-284.77.1.rt14.362.el9_2, kernel-rt-debug-5.14.0-284.77.1.rt14.362.el9_2 +9
    • Red Hat Enterprise Linux Real Time for NFV EUS (v.9.2) kernel-rt-5.14.0-284.77.1.rt14.362.el9_2, kernel-rt-core-5.14.0-284.77.1.rt14.362.el9_2, kernel-rt-debug-5.14.0-284.77.1.rt14.362.el9_2 +11
  • RHSA-2024:4928 Released 2024-07-31 · Red Hat rating Moderate
    kernel security update
    • Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-427.28.1.el9_4, kernel-64k-debug-devel-matched-5.14.0-427.28.1.el9_4, kernel-64k-devel-5.14.0-427.28.1.el9_4 +11
    • Red Hat Enterprise Linux BaseOS (v. 9) bpftool-7.3.0-427.28.1.el9_4, kernel-5.14.0-427.28.1.el9_4, kernel-64k-5.14.0-427.28.1.el9_4 +29
    • Red Hat Enterprise Linux CRB (v. 9) kernel-tools-libs-devel-5.14.0-427.28.1.el9_4, libperf-5.14.0-427.28.1.el9_4
    • Red Hat Enterprise Linux NFV (v. 9) kernel-rt-5.14.0-427.28.1.el9_4, kernel-rt-core-5.14.0-427.28.1.el9_4, kernel-rt-debug-5.14.0-427.28.1.el9_4 +11
    • Red Hat Enterprise Linux RT (v. 9) kernel-rt-5.14.0-427.28.1.el9_4, kernel-rt-core-5.14.0-427.28.1.el9_4, kernel-rt-debug-5.14.0-427.28.1.el9_4 +9

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 7AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 9AffectedNo fix yet
Red Hat CodeReady Linux Builder EUS (v.9.2)Fixed RHSA-2024:5066
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2024:4928
Red Hat Enterprise Linux AppStream EUS (v.9.2)Fixed RHSA-2024:5066
Red Hat Enterprise Linux BaseOS (v. 9)Fixed RHSA-2024:4928
Red Hat Enterprise Linux BaseOS EUS (v.9.2)Fixed RHSA-2024:5066
Red Hat Enterprise Linux CRB (v. 9)Fixed RHSA-2024:4928
Red Hat Enterprise Linux NFV (v. 9)Fixed RHSA-2024:4928
Red Hat Enterprise Linux RT (v. 9)Fixed RHSA-2024:4928
Red Hat Enterprise Linux Real Time EUS (v.9.2)Fixed RHSA-2024:5067
Red Hat Enterprise Linux Real Time for NFV EUS (v.9.2)Fixed RHSA-2024:5067
Not affected: 3 products
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 8
  • Red Hat Enterprise Linux AppStream EUS (v.9.2)

Timeline

  1. 2026-10-02 Threatist record created from CVE-2024-26737
  2. 2026-10-03 Alias added: GHSA-8x8h-8p2w-8g4f

References

Patch 5

  • 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