Vulnerability in Linux kernel (CVE-2026-98738)
Summary
Vulnerability in Linux kernel (CVE-2026-98738). 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: Serialize SMP remote OOB data access
build_pairing_cmd() looks up remote OOB data and copies its contents
without holding hdev->lock, which serializes the list's writers. After
SMP finds an entry, a concurrent management Remove Remote OOB Data
command can unlink and free it before SMP reads its present flag or
copies its random and confirmation values. Removal can also invalidate
an entry while the lookup is still traversing the list.
KASAN reported:
BUG: KASAN: slab-use-after-free in build_pairing_cmd+0x948/0x9b0
Call Trace:
build_pairing_cmd+0x948/0x9b0
smp_recv_cb+0x459f/0x8110
l2cap_recv_frame+0xf14/0x9190
l2cap_recv_acldata+0xa64/0xd40
hci_rx_work+0x4ca/0x730
Allocated by task 87:
hci_add_remote_oob_data+0x11d/0x530
add_remote_oob_data+0x282/0x400
hci_sock_sendmsg+0x1033/0x1ea0
Freed by task 93:
hci_remote_oob_data_clear+0x108/0x1c0
remove_remote_oob_data+0x198/0x220
hci_sock_sendmsg+0x1033/0x1ea0
Taking hdev->lock in build_pairing_cmd() would recurse for callers that
already hold it and invert the device-to-L2CAP lock order on the receive
path. Add a per-device remote_oob_lock instead, held across the SMP
lookup and copies and by the add, remove and clear helpers. Cover
initialization and in-place updates as well, so SMP cannot read partially
initialized or updated OOB values. Release the mutex on allocation
failure, preserving the existing erro…
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-2026-98738 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-2026-98738" on the vendor's site.
CVE-2026-98738 (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-2026-98738 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