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TI-2026-75861 Aliases CVE-2026-98733GHSA-25g3-wm5v-78g8

Race condition in Linux Bluetooth ISO queueing causes use-after-free

Priority LOW 22Published · Updated

Key facts

Attack vector
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Privileges required
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User interaction
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Attack complexity
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Impact type
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Confidentiality · integrity · availability
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Fix status
Partial Red Hat: 1 without a fix

No CVSS vector from any source. Fix status from CNA and Red Hat.

Summary

The Linux kernel Bluetooth ISO code adds fragmented packets to a queue without holding its lock, so the transmit worker can dequeue and free a packet that is still being linked. This leads to a use-after-free and queue corruption. A local user who can send data on an ISO socket can trigger it. Affected are Linux kernel versions from 6.0 before the fixed versions listed in the solution.

Written with Claude Haiku 5.5 from the sources below · 2026-10-30

Description from the CNA

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_core: Serialize fragmented ISO packet queueing The fragmented path in hci_queue_iso() calls __skb_queue_tail() without holding conn->data_q.lock. The socket lock serializes senders, but the transmit worker can concurrently remove packets from this queue using skb_dequeue(). After an insertion saves the old tail pointer, hci_sched_iso() can dequeue that packet and pass it to the driver. The driver can free the packet before the insertion resumes and writes to the old tail's next pointer, causing a use-after-free. Concurrent updates can also corrupt the queue. KASAN reported: BUG: KASAN: slab-use-after-free in hci_send_iso+0xc7d/0xe10 Call Trace: hci_send_iso+0xc7d/0xe10 iso_sock_sendmsg+0x710/0x900 __sys_sendto+0x34a/0x3a0 Allocated by task 86: __alloc_skb+0xdd/0x820 alloc_skb_with_frags+0x7e/0x770 sock_alloc_send_pskb+0x67a/0x820 bt_skb_sendmsg.constprop.0+0xc0/0x6c0 iso_sock_sendmsg+0x44e/0x900 Freed by task 90: kmem_cache_free+0xcb/0x3d0 vhci_read+0x33f/0x4d0 vfs_read+0x177/0xa20 Hold the queue lock across the entire fragment batch, as hci_queue_acl() does, to serialize insertion against dequeue while preserving fragment ordering.

Why it matters now

EPSS 0.00172 6th percentileScored 2026-11-07
Fix Partial Linux (Linux): 6.1.191, 6.6.160, 6.12.113 +3Red Hat: 1 without a fix

SSVC decision points

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

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux6.0 and later6.1.191, 6.6.160, 6.12.113, 6.18.56, 7.2.10, 7.3Patch availableCNA
  • Linux VendorLinux Affected 6.0 and later Fixed in 6.1.191, 6.6.160, 6.12.113, 6.18.56, 7.2.10, 7.3 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*——Linux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions — — ·Linux

Remediation

Upgrade the Linux kernel to 6.1.191, 6.6.160, 6.12.113, 6.18.56, 7.2.10 or 7.3, matching the stable branch in use. The sources list no fixed version for Red Hat Enterprise Linux 10.

Written with Claude Haiku 5.5 from the sources below · 2026-10-30

  • Fix · CNA Linux (Linux) Fixed in 6.1.191, 6.6.160, 6.12.113, 6.18.56, 7.2.10, 7.3

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 10AffectedNo fix yet: Fix deferred

Timeline

  1. 2026-10-18 Threatist record created from CVE-2026-98733
  2. 2026-10-18 Alias added: GHSA-25g3-wm5v-78g8
  3. 2026-10-19 Fix available: Linux/[email protected] · CNA
  4. 2026-10-21 Affected versions changed · Red Hat
  5. 2026-10-21 CVSS score added · Red Hat
  6. 2026-10-21 Fix available: Linux/Linux@545fa70f730eb648a610a2f4b2d270865f77b619, Linux/[email protected] · CNA
  7. 2026-10-21 1 new reference · CNA
  8. 2026-10-30 Fix available: Linux/[email protected], Linux/Linux@e328b5823fa6b0b160d0922d6d68323e910d09a4 · CNA
  9. 2026-10-30 1 new reference · CNA

References

  • 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
See all 21741 →

Sources