Vulnerability in Linux kernel (CVE-2026-43097)
Summary
Vulnerability in Linux kernel (CVE-2026-43097). Successful exploitation can lead to full system takeover.
Original description
The description as published by the source.
In the Linux kernel, the following vulnerability has been resolved:
PCI: hv: Fix double ida_free in hv_pci_probe error path
If hv_pci_probe() fails after storing the domain number in
hbus->bridge->domain_nr, there is a call to free this domain_nr via
pci_bus_release_emul_domain_nr(), however, during cleanup, the bridge
release callback pci_release_host_bridge_dev() also frees the domain_nr
causing ida_free to be called on same ID twice and triggering following
warning:
ida_free called for id=28971 which is not allocated.
WARNING: lib/idr.c:594 at ida_free+0xdf/0x160, CPU#0: kworker/0:2/198
Call Trace:
pci_bus_release_emul_domain_nr+0x17/0x20
pci_release_host_bridge_dev+0x4b/0x60
device_release+0x3b/0xa0
kobject_put+0x8e/0x220
devm_pci_alloc_host_bridge_release+0xe/0x20
devres_release_all+0x9a/0xd0
device_unbind_cleanup+0x12/0xa0
really_probe+0x1c5/0x3f0
vmbus_add_channel_work+0x135/0x1a0
Fix this by letting pci core handle the free domain_nr and remove
the explicit free called in pci-hyperv driver.
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-2026-43097 has been found in Linux kernel.
Successful exploitation can lead to full system takeover. CVSS score: 7.8/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Linux kernel CVE-2026-43097" on the vendor's site.
CVE-2026-43097 (Linux kernel) — CWE-415 / CVSS v3 7.8
Attack vector: local / 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 (CWE-415) exists in Linux kernel.
Check the vendor advisory for the affected versions of Linux kernel.
Severity: High (CVSS 7.8/10). Successful exploitation can lead to full system takeover.
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-2026-43097
- Debian DEBIAN-CVE-2026-43097 linux Fixed in: 6.19.14-1
- Ubuntu UBUNTU-CVE-2026-43097 linux-hwe-edge
References
- advisory nvd.nist.gov
- advisory github.com
- package git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web github.com