Vulnerability in Linux kernel (CVE-2026-98734)
Summary
Vulnerability in Linux kernel (CVE-2026-98734). Risk of unauthorized operations or information disclosure.
Original description
The description as published by the source.
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: hci_core: Serialize SCO and ISO scheduling with teardown
hci_low_sent() selects a connection under RCU but drops the read lock
before calculating its quota and returning it to the scheduler. The
connection is then used without lifetime protection by hci_sched_iso()
and hci_sched_sco().
After the TX worker drops the RCU read lock, hci_abort_conn_sync() on
hdev->req_workqueue can remove the connection from the hash, complete
synchronize_rcu(), purge its queues and release it. The TX worker on
hdev->workqueue can then access the freed connection in hci_quote_sent()
or while dequeuing packets and updating conn->sent.
KASAN reported:
BUG: KASAN: slab-use-after-free in hci_low_sent+0x730/0x840
Workqueue: hci0 hci_tx_work
Call Trace:
hci_low_sent+0x730/0x840
hci_sched_iso+0x25e/0x4d0
hci_tx_work+0x239/0xcb0
Allocated by task 93:
__hci_conn_add+0x16f/0x1b40
hci_bind_bis+0x782/0x17b0
hci_connect_bis+0xa0/0x510
iso_sock_connect+0x589/0x1050
Freed by task 88:
kfree+0x131/0x3c0
device_release+0xc8/0x240
kobject_put+0x14d/0x280
hci_conn_del+0x55a/0xe80
hci_disconnect_sync+0x156/0x180
hci_abort_conn_sync+0x3e7/0x940
hci_cmd_sync_work+0x13c/0x290
Hold hci_dev_lock() across connection selection and transmission in both
SCO and ISO scheduling, serializing them with connection teardown. This
also prevents queuing completion timestamps after the connection q…
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-98734 has been found in Linux kernel.
Risk of unauthorized operations or information disclosure.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Linux kernel CVE-2026-98734" on the vendor's site.
CVE-2026-98734 (Linux kernel)
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (unclassified) exists in Linux kernel.
Check the vendor advisory for the affected versions of Linux kernel.
Severity: ?. Risk of unauthorized operations or information disclosure.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで Linux kernel を使っているサービスとバージョンを洗い出す。
-
2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Debian DEBIAN-CVE-2026-98734 linux
References
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web nvd.nist.gov
- web github.com