Vulnerability in Linux kernel (CVE-2026-98735)
Summary
Vulnerability in Linux kernel (CVE-2026-98735). 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 ACL scheduling with channel deletion
hci_chan_sent() selects a channel under RCU but drops the read lock before
accessing chan->conn and returning the channel. The ACL and LE schedulers
then use its packet queue and update its transmit counters without any
protection against channel deletion.
After TX selects a channel and releases RCU, a disconnect command timeout
on the separate request workqueue can run hci_conn_failed() and
l2cap_conn_del(). hci_chan_del() can then unlink the channel, complete
synchronize_rcu(), purge its queue and free it before TX resumes. This
causes use-after-free both in hci_chan_sent() and in its callers.
KASAN reported:
BUG: KASAN: slab-use-after-free in hci_chan_sent+0x892/0x9b0
Workqueue: hci0 hci_tx_work
Call Trace:
hci_chan_sent+0x892/0x9b0
hci_tx_work+0x5e6/0xb70
Allocated by task 91:
hci_chan_create+0xe3/0x350
l2cap_conn_add.part.0+0x12/0xa30
l2cap_chan_connect+0x110d/0x1b60
l2cap_sock_connect+0x310/0x530
Freed by task 99:
hci_chan_del+0x11f/0x170
l2cap_conn_del+0x4f1/0x800
l2cap_connect_cfm+0x88c/0xd30
hci_conn_failed+0x150/0x250
hci_abort_conn_sync+0x3e3/0x800
hci_cmd_sync_run+0x7e/0xc0
hci_abort_conn+0x105/0x1f0
disconnect_sync+0x157/0x290
hci_cmd_sync_work+0x13c/0x290
Hold the existing device mutex across channel selection and transmission
in both schedulers to serialize them with…
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-2026-98735 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-2026-98735" on the vendor's site.
CVE-2026-98735 (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-2026-98735 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