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TI-2026-24328 Aliases CVE-2026-31772GHSA-9f4r-27xr-gwq3

Bluetooth: hci_sync: fix stack buffer overflow in hci_le_big_create_sync

Priority LOW 35CWE-121Published · 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-121 and the CVSS impact.

Summary

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_sync: fix stack buffer overflow in hci_le_big_create_sync hci_le_big_create_sync() uses DEFINE_FLEX to allocate a struct hci_cp_le_big_create_sync on the stack with room for 0x11 (17) BIS entries. However, conn->num_bis can hold up to HCI_MAX_ISO_BIS (31) entries — validated against ISO_MAX_NUM_BIS (0x1f) in the caller hci_conn_big_create_sync(). When conn->num_bis is between 18 and 31, the memcpy that copies conn->bis into cp->bis writes up to 14 bytes past the stack buffer, corrupting adjacent stack memory. This is trivially reproducible: binding an ISO socket with bc_num_bis = ISO_MAX_NUM_BIS (31) and calling listen() will eventually trigger hci_le_big_create_sync() from the HCI command sync worker, causing a KASAN-detectable stack-out-of-bounds write: BUG: KASAN: stack-out-of-bounds in hci_le_big_create_sync+0x256/0x3b0 Write of size 31 at addr ffffc90000487b48 by task kworker/u9:0/71 Fix this by changing the DEFINE_FLEX count from the incorrect 0x11 to HCI_MAX_ISO_BIS, which matches the maximum number of BIS entries that conn->bis can actually carry.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00142 3rd percentileScored 2026-11-07
Fix Fixed Linux (Linux): 6.12.81, 6.12, 6.18.22 +2Red Hat: 3 advisories

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

VendorProductAffected versionsFixed inStatusSource
LinuxLinux6.12.2 to before 6.12.81; 6.11.11 to before 6.126.12.81, 6.12Patch availableCNA
LinuxLinux6.13 and later6.12.81, 6.18.22, 6.19.12, 7.0Patch availableCNA
  • Linux VendorLinux Affected 6.12.2 to before 6.12.81; 6.11.11 to before 6.12 Fixed in 6.12.81, 6.12 Patch available CNA
  • Linux VendorLinux Affected 6.13 and later Fixed in 6.12.81, 6.18.22, 6.19.12, 7.0 Patch available CNA

CPE configurations NVD · 8

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*6.11.11 to before 6.12; 6.12.2 to before 6.12.81; 6.13.1 to before 6.18.22; 6.19 to before 6.19.12VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.13:-:*:*:*:*:*:*6.13VulnerableLinux
cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*7.0 rc1VulnerableLinux
cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:*7.0 rc2VulnerableLinux
cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:*7.0 rc3VulnerableLinux
cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:*7.0 rc4VulnerableLinux
cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:*7.0 rc5VulnerableLinux
cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:*7.0 rc6VulnerableLinux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 6.11.11 to before 6.12; 6.12.2 to before 6.12.81; 6.13.1 to before 6.18.22; 6.19 to before 6.19.12 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.13:-:*:*:*:*:*:* Versions 6.13 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:* Versions 7.0 rc1 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:* Versions 7.0 rc2 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:* Versions 7.0 rc3 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:* Versions 7.0 rc4 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:* Versions 7.0 rc5 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:* Versions 7.0 rc6 Vulnerable ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 6.12.81, 6.12
  • Fix · CNA Linux (Linux) Fixed in 6.12.81, 6.18.22, 6.19.12, 7.0

Red Hat 3 advisories

  • RHSA-2026:83707 Released 2026-10-16 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream EUS (v. 10.0) kernel-64k-debug-devel-6.12.0-55.111.1.el10_0, kernel-64k-debug-devel-matched-6.12.0-55.111.1.el10_0, kernel-64k-devel-6.12.0-55.111.1.el10_0 +12
    • Red Hat Enterprise Linux BaseOS EUS (v. 10.0) kernel-6.12.0-55.111.1.el10_0, kernel-64k-6.12.0-55.111.1.el10_0, kernel-64k-core-6.12.0-55.111.1.el10_0 +28
    • Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0) kernel-tools-libs-devel-6.12.0-55.111.1.el10_0, libperf-6.12.0-55.111.1.el10_0
    • Red Hat Enterprise Linux Real Time EUS (v. 10.0) kernel-rt-6.12.0-55.111.1.el10_0, kernel-rt-64k-6.12.0-55.111.1.el10_0, kernel-rt-64k-core-6.12.0-55.111.1.el10_0 +21
    • Red Hat Enterprise Linux Real Time for NFV EUS (v. 10.0) kernel-rt-6.12.0-55.111.1.el10_0, kernel-rt-core-6.12.0-55.111.1.el10_0, kernel-rt-debug-6.12.0-55.111.1.el10_0 +11
  • RHSA-2026:27789 Released 2026-06-22 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-687.17.1.el9_8, kernel-64k-debug-devel-matched-5.14.0-687.17.1.el9_8, kernel-64k-devel-5.14.0-687.17.1.el9_8 +12
    • Red Hat Enterprise Linux BaseOS (v. 9) kernel-5.14.0-687.17.1.el9_8, kernel-64k-5.14.0-687.17.1.el9_8, kernel-64k-core-5.14.0-687.17.1.el9_8 +28
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) kernel-tools-libs-devel-5.14.0-687.17.1.el9_8, libperf-5.14.0-687.17.1.el9_8
    • Red Hat Enterprise Linux Real Time (v. 9) kernel-rt-5.14.0-687.17.1.el9_8, kernel-rt-64k-5.14.0-687.17.1.el9_8, kernel-rt-64k-core-5.14.0-687.17.1.el9_8 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 9) kernel-rt-5.14.0-687.17.1.el9_8, kernel-rt-core-5.14.0-687.17.1.el9_8, kernel-rt-debug-5.14.0-687.17.1.el9_8 +9
  • RHSA-2026:27288 Released 2026-06-20 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream (v. 10) kernel-64k-debug-devel-6.12.0-211.26.1.el10_2, kernel-64k-debug-devel-matched-6.12.0-211.26.1.el10_2, kernel-64k-devel-6.12.0-211.26.1.el10_2 +12
    • Red Hat Enterprise Linux BaseOS (v. 10) kernel-6.12.0-211.26.1.el10_2, kernel-64k-6.12.0-211.26.1.el10_2, kernel-64k-core-6.12.0-211.26.1.el10_2 +29
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) kernel-tools-libs-devel-6.12.0-211.26.1.el10_2, libperf-6.12.0-211.26.1.el10_2
    • Red Hat Enterprise Linux Real Time (v. 10) kernel-rt-6.12.0-211.26.1.el10_2, kernel-rt-64k-6.12.0-211.26.1.el10_2, kernel-rt-64k-core-6.12.0-211.26.1.el10_2 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 10) kernel-rt-6.12.0-211.26.1.el10_2, kernel-rt-core-6.12.0-211.26.1.el10_2, kernel-rt-debug-6.12.0-211.26.1.el10_2 +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-2026:27288
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2026:27789
Red Hat Enterprise Linux AppStream EUS (v. 10.0)Fixed RHSA-2026:83707
Red Hat Enterprise Linux BaseOS (v. 10)Fixed RHSA-2026:27288
Red Hat Enterprise Linux BaseOS (v. 9)Fixed RHSA-2026:27789
Red Hat Enterprise Linux BaseOS EUS (v. 10.0)Fixed RHSA-2026:83707
Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)Fixed RHSA-2026:27288
Red Hat Enterprise Linux CodeReady Linux Builder (v. 9)Fixed RHSA-2026:27789
Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0)Fixed RHSA-2026:83707
Red Hat Enterprise Linux Real Time (v. 10)Fixed RHSA-2026:27288
Red Hat Enterprise Linux Real Time (v. 9)Fixed RHSA-2026:27789
Red Hat Enterprise Linux Real Time EUS (v. 10.0)Fixed RHSA-2026:83707
Red Hat Enterprise Linux Real Time for NFV (v. 10)Fixed RHSA-2026:27288
Red Hat Enterprise Linux Real Time for NFV (v. 9)Fixed RHSA-2026:27789
Red Hat Enterprise Linux Real Time for NFV EUS (v. 10.0)Fixed RHSA-2026:83707
Not affected: 4 products
  • 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-2026-31772
  2. 2026-10-03 Alias added: GHSA-9f4r-27xr-gwq3
  3. 2026-10-16 CISA SSVC decision points changed
  4. 2026-10-18 Fix available: RHSA-2026:83707 · Red Hat
  5. 2026-10-18 Fix available: Red Hat Enterprise Linux AppStream EUS (v. 10.0), Red Hat Enterprise Linux BaseOS EUS (v. 10.0), Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0) +2 · Red Hat
  6. 2026-10-19 Weakness changed · CISA ADP
  7. 2026-10-29 Affected versions changed · Red Hat

References

Patch 4

  • 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