Vulnerability in Kernel (CVE-2026-23085)

Summary

Vulnerability in Kernel (CVE-2026-23085). Risk of unauthorized operations or information disclosure. Mitigation: upgrade to 5.10.249, 5.15.199, 6.1.162, 6.6.122, 6.12.68, 6.18.8 or later.

Original description

The description as published by the source.

In the Linux kernel, the following vulnerability has been resolved:

irqchip/gic-v3-its: Avoid truncating memory addresses

On 32-bit machines with CONFIG_ARM_LPAE, it is possible for lowmem
allocations to be backed by addresses physical memory above the 32-bit
address limit, as found while experimenting with larger VMSPLIT
configurations.

This caused the qemu virt model to crash in the GICv3 driver, which
allocates the 'itt' object using GFP_KERNEL. Since all memory below
the 4GB physical address limit is in ZONE_DMA in this configuration,
kmalloc() defaults to higher addresses for ZONE_NORMAL, and the
ITS driver stores the physical address in a 32-bit 'unsigned long'
variable.

Change the itt_addr variable to the correct phys_addr_t type instead,
along with all other variables in this driver that hold a physical
address.

The gicv5 driver correctly uses u64 variables, while all other irqchip
drivers don't call virt_to_phys or similar interfaces. It's expected that
other device drivers have similar issues, but fixing this one is
sufficient for booting a virtio based guest.

Source: OSV.dev (Open Source Vulnerabilities) NVD OSV

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-2026-23085 has been found in Kernel.
Risk of unauthorized operations or information disclosure.
What to do: upgrade Kernel to 5.10.249, 5.15.199, 6.1.162, 6.6.122, 6.12.68, 6.18.8 or later.
If unsure, ask your IT team or search "Kernel CVE-2026-23085" on the vendor's site.

CVE-2026-23085 (Kernel)
Patched: 5.10.249, 5.15.199, 6.1.162, 6.6.122, 6.12.68, 6.18.8 — apply immediately
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.

❓ What is the problem

A vulnerability (unclassified) exists in Kernel.

📍 Affected scope

Check the vendor advisory for the affected versions of Kernel.

🔥 Severity

Severity: ?. Risk of unauthorized operations or information disclosure.

🔧 How to fix

Update to 5.10.249, 5.15.199, 6.1.162, 6.6.122, 6.12.68, 6.18.8.

🛡️ Workaround

Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.

🔍 Detection

Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'Kernel' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.

Response actions

Concrete steps and command examples for SOC/SRE teams to execute in order

1
Identify exposure identify
```
grep -r 'Kernel' . | grep -v node_modules
```
リポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で Kernel を grep し、稼働しているサービス・バージョンを把握する。
2
Apply patch patch
```
Upgrade Kernel to 5.10.249, 5.15.199, 6.1.162, 6.6.122, 6.12.68, 6.18.8
```
ステージング環境で 5.10.249, 5.15.199, 6.1.162, 6.6.122, 6.12.68, 6.18.8 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
3
Post-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

Linux Kernel

[{"type":"ECOSYSTEM","events":[{"introduced":"3.19.0"},{"fixed":"5.10.249"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.199"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.162"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.122"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.68"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.8"}]}]

Fix status by distribution

Fixed packages published by each distribution for this CVE

BellSoft Alpaquita BELL-CVE-2026-23085 linux-lts Fixed in: 6.1.163-r0
Debian DEBIAN-CVE-2026-23085 linux Fixed in: 5.10.249-1
Ubuntu UBUNTU-CVE-2026-23085 linux-aws