Vulnerability in Linux kernel (CVE-2026-80682)
Summary
Vulnerability in Linux kernel (CVE-2026-80682). 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:
riscv/mm: use physical alignment for vmemmap_start_pfn
RISC-V computes vmemmap_start_pfn by rounding phys_ram_base down to
VMEMMAP_ADDR_ALIGN. That alignment must therefore be expressed in the
physical-address domain.
Commit 476849b0fba4 ("riscv/mm: align vmemmap to maximal folio size")
attempted to account for the maximal folio alignment by feeding
MAX_FOLIO_VMEMMAP_ALIGN directly into VMEMMAP_ADDR_ALIGN. However,
MAX_FOLIO_VMEMMAP_ALIGN is measured in bytes of struct page storage,
whereas VMEMMAP_ADDR_ALIGN is used to align a physical address.
The mask-based compound_info encoding requires pfn_to_page(0) to be
naturally aligned to MAX_FOLIO_VMEMMAP_ALIGN. Commit 9f94db4c7eaa
("mm/sparse: check memmap alignment for compound_info_has_mask()") added a
check for that requirement and exposed the unit mismatch on systems such
as QEMU virt, where the DRAM base is not aligned to MAX_FOLIO_NR_PAGES *
PAGE_SIZE.
Here is the log:
[ 0.000000][ C0] ------------[ cut here ]------------
[ 0.000000][ C0] WARNING: mm/sparse.c:365 at sparse_init+0x58a/0x6fe, CPU#0: swapper/0
[ 0.000000][ C0] Modules linked in:
[ 0.000000][ C0] CPU: 0 UID: 0 PID: 0 Comm: swapper Not tainted 7.2.0-rc3-g1d8304bdd65f #2 PREEMPT
[ 0.000000][ C0] Hardware name: riscv-virtio,qemu (DT)
[ 0.000000][ C0] epc : sparse_init+0x58a/0x6fe
[ 0.000000][ C0] ra : sparse_init+0x58a/0x6fe
[ 0.000000][ C0…
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-2026-80682 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-2026-80682" on the vendor's site.
CVE-2026-80682 (Linux kernel) — 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 (unclassified) 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-2026-80682
- Debian DEBIAN-CVE-2026-80682 linux Fixed in: 7.1.8-1
- Ubuntu UBUNTU-CVE-2026-80682 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