Vulnerability in Linux kernel (CVE-2026-90212)
Summary
Vulnerability in Linux kernel (CVE-2026-90212). 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:
arm64/efi: Avoid voluntary preemption with efi_mm installed
Gus reports a bad kernel memory access when using software PAN
(CONFIG_ARM64_SW_TTBR0_PAN=y) on a machine with support for EFI runtime
services:
Unable to handle kernel access to user memory outside uaccess routines
at virtual address 00000000f322ff30
Mem abort info:
ESR = 0x0000000096000004
FSC = 0x04: level 0 translation fault
Internal error: Oops: 0000000096000004 [#1] SMP
Workqueue: efi_rts_wq efi_call_rts
pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : efi_call_rts+0xd8/0x288
Call trace:
efi_call_rts+0xd8/0x288 (P)
process_one_work+0x178/0x4f8
worker_thread+0x194/0x328
This is because the fpsimd context management code called from
__efi_fpsimd_begin() can preempt voluntarily, returning later to the EFI
code with an incorrect value for TTBR0_EL1 thanks to the deferred mm
switching used by the software PAN implementation.
Since EFI runtime services cannot preempt voluntarily and because the
fpsimd switching code does not rely on the TTBR0_EL1 mappings, simply
reorder the fpsimd switch so that it occurs before we change the
page-table.
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-2026-90212 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-2026-90212" on the vendor's site.
CVE-2026-90212 (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-2026-90212 linux Fixed in: 7.2.6-1
- Ubuntu UBUNTU-CVE-2026-90212 linux-hwe-edge
References
- web git.kernel.org
- web git.kernel.org
- web nvd.nist.gov
- web github.com