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TI-2025-15801 Aliases CVE-2025-21851GHSA-hc84-56cx-wr29

bpf: Fix softlockup in arena_map_free on 64k page kernel

Priority LOW 33CWE-667Published · 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
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-667 and the CVSS impact.

Summary

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix softlockup in arena_map_free on 64k page kernel On an aarch64 kernel with CONFIG_PAGE_SIZE_64KB=y, arena_htab tests cause a segmentation fault and soft lockup. The same failure is not observed with 4k pages on aarch64. It turns out arena_map_free() is calling apply_to_existing_page_range() with the address returned by bpf_arena_get_kern_vm_start(). If this address is not page-aligned the code ends up calling apply_to_pte_range() with that unaligned address causing soft lockup. Fix it by round up GUARD_SZ to PAGE_SIZE << 1 so that the division by 2 in bpf_arena_get_kern_vm_start() returns a page-aligned value.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00177 7th percentileScored 2026-11-07
Fix Fixed Linux (Linux): 6.12.17, 6.13.5, 6.14Red Hat: 2 advisories

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
LinuxLinux6.9 and later6.12.17, 6.13.5, 6.14Patch availableCNA
  • Linux VendorLinux Affected 6.9 and later Fixed in 6.12.17, 6.13.5, 6.14 Patch available CNA

CPE configurations NVD · 5

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*6.9 to before 6.12.17; 6.13 to before 6.13.5VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.9:-:*:*:*:*:*:*6.9VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.14:rc1:*:*:*:*:*:*6.14 rc1VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.14:rc2:*:*:*:*:*:*6.14 rc2VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.14:rc3:*:*:*:*:*:*6.14 rc3VulnerableLinux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 6.9 to before 6.12.17; 6.13 to before 6.13.5 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.9:-:*:*:*:*:*:* Versions 6.9 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.14:rc1:*:*:*:*:*:* Versions 6.14 rc1 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.14:rc2:*:*:*:*:*:* Versions 6.14 rc2 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.14:rc3:*:*:*:*:*:* Versions 6.14 rc3 Vulnerable ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 6.12.17, 6.13.5, 6.14

Red Hat 2 advisories

  • RHSA-2025:20518 Released 2025-11-11 · Red Hat rating Moderate
    kernel security update
    • Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-611.5.1.el9_7, kernel-64k-debug-devel-matched-5.14.0-611.5.1.el9_7, kernel-64k-devel-5.14.0-611.5.1.el9_7 +12
    • Red Hat Enterprise Linux BaseOS (v. 9) kernel-5.14.0-611.5.1.el9_7, kernel-64k-5.14.0-611.5.1.el9_7, kernel-64k-core-5.14.0-611.5.1.el9_7 +28
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) kernel-tools-libs-devel-5.14.0-611.5.1.el9_7, libperf-5.14.0-611.5.1.el9_7
    • Red Hat Enterprise Linux Real Time (v. 9) kernel-rt-5.14.0-611.5.1.el9_7, kernel-rt-64k-5.14.0-611.5.1.el9_7, kernel-rt-64k-core-5.14.0-611.5.1.el9_7 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 9) kernel-rt-5.14.0-611.5.1.el9_7, kernel-rt-core-5.14.0-611.5.1.el9_7, kernel-rt-debug-5.14.0-611.5.1.el9_7 +9
  • RHSA-2025:20095 Released 2025-11-11 · Red Hat rating Moderate
    kernel security update
    • Red Hat Enterprise Linux AppStream (v. 10) kernel-64k-debug-devel-6.12.0-124.8.1.el10_1, kernel-64k-debug-devel-matched-6.12.0-124.8.1.el10_1, kernel-64k-devel-6.12.0-124.8.1.el10_1 +12
    • Red Hat Enterprise Linux BaseOS (v. 10) kernel-6.12.0-124.8.1.el10_1, kernel-64k-6.12.0-124.8.1.el10_1, kernel-64k-core-6.12.0-124.8.1.el10_1 +29
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) kernel-tools-libs-devel-6.12.0-124.8.1.el10_1, libperf-6.12.0-124.8.1.el10_1
    • Red Hat Enterprise Linux Real Time (v. 10) kernel-rt-6.12.0-124.8.1.el10_1, kernel-rt-64k-6.12.0-124.8.1.el10_1, kernel-rt-64k-core-6.12.0-124.8.1.el10_1 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 10) kernel-rt-6.12.0-124.8.1.el10_1, kernel-rt-core-6.12.0-124.8.1.el10_1, kernel-rt-debug-6.12.0-124.8.1.el10_1 +9

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2025:20095
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2025:20518
Red Hat Enterprise Linux BaseOS (v. 10)Fixed RHSA-2025:20095
Red Hat Enterprise Linux BaseOS (v. 9)Fixed RHSA-2025:20518
Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)Fixed RHSA-2025:20095
Red Hat Enterprise Linux CodeReady Linux Builder (v. 9)Fixed RHSA-2025:20518
Red Hat Enterprise Linux Real Time (v. 10)Fixed RHSA-2025:20095
Red Hat Enterprise Linux Real Time (v. 9)Fixed RHSA-2025:20518
Red Hat Enterprise Linux Real Time for NFV (v. 10)Fixed RHSA-2025:20095
Red Hat Enterprise Linux Real Time for NFV (v. 9)Fixed RHSA-2025:20518
Not affected: 3 products
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-21851
  2. 2026-10-03 Alias added: GHSA-hc84-56cx-wr29
  3. 2026-10-29 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