Ubuntu Linux Kernel Update for Raspberry Pi Fixes Three Vulnerabilities
Tech GuruQuick Answer
Ubuntu USN-8851-2 updates the Ubuntu 18.04 ESM Raspberry Pi 5.4 kernel for three vulnerabilities. The fixed versioned binary is linux-image-5.4.0-1147-raspi 5.4.0-1147.160~18.04.1; linux-raspi-5.4 is source provenance, not the install command. Use the matching supported kernel packages, then reboot.
Confirm Scope And Apply The Supported Fix
What to do now: Inventory Ubuntu 18.04 ESM Raspberry Pi kernel, match the exact affected release or feature, apply the authority-supported fixed build or service remediation, validate the dependent workflow, and preserve evidence.
Last verified: 2026-10-02 UTC. Recheck the authoritative advisory and supported distribution channel before changing production.
Scope And Authority
| Product scope | Ubuntu 18.04 ESM Raspberry Pi kernel |
|---|---|
| Advisory | USN-8851-2 |
| CVEs | CVE-2025-38724, CVE-2026-53131, CVE-2026-53221 |
| Authoritative release date | 2026-10-02 06:30:35.580450 UTC |
| Authority revision date | No separate material revision date is stated by Ubuntu; verified against the first-party notice API |
| Affected versions | The linux-raspi-5.4 source package on Ubuntu 18.04 ESM before the notice-listed build. |
| Fixed source build (not an install command) | Ubuntu 18.04 ESM: linux-raspi-5.4 5.4.0-1147.160~18.04.1 |
| CVSS base score | Not provided by the authority |
| CVSS severity | Not provided by the authority |
| Exploitation status | Not stated by the authority; no exploitation claim is inferred. |
What Changed
Canonical identifies NFS server, IPv6 and Netfilter flaws. Applicability is to the listed bionic Raspberry Pi kernel stream, not Raspberry Pi OS or every Ubuntu kernel. The notice does not provide a per-deployment exploit assessment.
Fixed Binary Packages
Canonical's notice API lists these visible binary fixes. Match installed packages; this is not an instruction to install every listed package.
- bionic:
linux-image-5.4.0-1147-raspi 5.4.0-1147.160~18.04.1;linux-image-raspi-5.4 5.4.0.1147.160~18.04.1;linux-image-raspi-hwe-18.04 5.4.0.1147.160~18.04.1.
What To Validate Now
- Inventory. Locate Ubuntu 18.04 ESM Raspberry Pi kernel deployments, versions, enabled features, exposure paths, owners, and dependent services.
- Establish applicability. Match the installed Ubuntu release and binary packages to USN-8851-2. The source build identifies packaging provenance; it is not necessarily an installable package name. Do not transfer a version from another release or assume bundled upstream software is covered.
- Remediate. Update the installed raspi kernel image and applicable metapackage from the entitled bionic ESM repository. Keep the versioned image and metapackage versions distinct, as listed below. Prepare recovery access, rebuild/reinstall third-party modules affected by the ABI change, and reboot into the corrected kernel.
- Validate. After reboot, verify the running raspi kernel, required module loading, boot storage and normal network access. Check any NFS or firewall-dependent workload actually used by the Pi. Keep a controlled recovery path, but do not treat returning to the vulnerable kernel as completed remediation.
- Retain evidence. Preserve asset and owner identifiers, the applicability decision, before-and-after versions, change approval, installation output, validation results, and any exception or rollback record.
Operational Cautions
The authority states that these updates change the kernel ABI. Confirm Ubuntu Pro or ESM entitlement where required, inventory third-party kernel modules, coordinate reboots, test boot and recovery paths, and retain the prior kernel for controlled rollback.
Evidence To Retain
- Exact product, release stream, package or application version, enabled feature, environment, and accountable owner.
- UTC timestamps, authority revision, approved change record, installer or package-manager output, and resulting version.
- Relevant logs and monitoring evidence, test results, exceptions, compensating controls, and rollback decisions.
Related TechGeeks Resources
Authoritative References
Correction policy: If the authority changes affected versions, fixed versions, severity, exploitation information, mitigations, or required action, TechGeeks will update this notice and its verification date.
