Vulnerability in Linux kernel (CVE-2026-43199)
Summary
Vulnerability in Linux kernel (CVE-2026-43199). 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:
net/mlx5e: Fix "scheduling while atomic" in IPsec MAC address query
Fix a "scheduling while atomic" bug in mlx5e_ipsec_init_macs() by
replacing mlx5_query_mac_address() with ether_addr_copy() to get the
local MAC address directly from netdev->dev_addr.
The issue occurs because mlx5_query_mac_address() queries the hardware
which involves mlx5_cmd_exec() that can sleep, but it is called from
the mlx5e_ipsec_handle_event workqueue which runs in atomic context.
The MAC address is already available in netdev->dev_addr, so no need
to query hardware. This avoids the sleeping call and resolves the bug.
Call trace:
BUG: scheduling while atomic: kworker/u112:2/69344/0x00000200
__schedule+0x7ab/0xa20
schedule+0x1c/0xb0
schedule_timeout+0x6e/0xf0
__wait_for_common+0x91/0x1b0
cmd_exec+0xa85/0xff0 [mlx5_core]
mlx5_cmd_exec+0x1f/0x50 [mlx5_core]
mlx5_query_nic_vport_mac_address+0x7b/0xd0 [mlx5_core]
mlx5_query_mac_address+0x19/0x30 [mlx5_core]
mlx5e_ipsec_init_macs+0xc1/0x720 [mlx5_core]
mlx5e_ipsec_build_accel_xfrm_attrs+0x422/0x670 [mlx5_core]
mlx5e_ipsec_handle_event+0x2b9/0x460 [mlx5_core]
process_one_work+0x178/0x2e0
worker_thread+0x2ea/0x430
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-2026-43199 has been found in Linux kernel.
Risk of unauthorized operations or information disclosure. CVSS score: 7.5/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Linux kernel CVE-2026-43199" on the vendor's site.
CVE-2026-43199 (Linux kernel) — CVSS v3 7.5
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
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: High (CVSS 7.5/10). 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。
Affected packages
Fix status by distribution
Fixed packages published by each distribution for this CVE
- BellSoft Alpaquita BELL-CVE-2026-43199 linux-lts Fixed in: 6.12.80-r0
- Debian DEBIAN-CVE-2026-43199 linux Fixed in: 6.12.85-1
- Ubuntu UBUNTU-CVE-2026-43199 linux-hwe-edge
References
- advisory nvd.nist.gov
- advisory github.com
- package git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web github.com