Critical USN-7755-2 Linux kernel (FIPS) security update patches 10+ vulnerabilities in Media drivers, SPI, USB, and networking. Learn the urgent update instructions, CVE details, and how Ubuntu Pro extends security coverage. Essential for Azure, GCP, and on-premise systems.
The Ubuntu security team has issued an urgent security notice, USN-7755-2, addressing multiple high-severity vulnerabilities within the FIPS-validated Linux kernel packages.
These security flaws, if exploited, could allow a local or remote attacker to gain elevated privileges, execute arbitrary code, or cause a denial-of-service condition on critical infrastructure systems.
This patch is mandatory for all enterprises operating on Ubuntu 18.04 LTS (Bionic Beaver) in Azure, Google Cloud, or on-premise environments requiring FIPS 140-2/140-3 compliance.
Detailed Overview of the Security Threats
The disclosed vulnerabilities span several critical subsystems of the Linux kernel, each representing a potential vector for a severe security breach. The affected areas include the kernel's handling of Media drivers, the SPI subsystem, the USB core drivers, the NILFS2 file system, IPv6 networking protocols, and Network traffic control mechanisms.
A successful exploit targeting any of these weaknesses could lead to a full system compromise, data exfiltration, or service disruption. For organizations adhering to strict compliance frameworks like FedRAMP, PCI DSS, or HIPAA, applying this patch is not just a best practice but a regulatory imperative to maintain a hardened security posture.
This update underscores a persistent challenge in cybersecurity: the constant need to patch foundational system software like the kernel.
Why is kernel security so paramount? Because the kernel operates at the highest privilege level (ring 0), a single vulnerability within it can undermine all other security controls deployed on a server.
Affected Packages and Update Instructions
The following FIPS-compliant kernel packages require immediate updating. The standard apt update && apt upgrade commands will fetch the necessary patches.
| Ubuntu Release | Package Name | Fixed Version |
|---|---|---|
| Ubuntu 18.04 LTS (Bionic) | linux-azure-fips | 4.15.0-2101.107 |
linux-fips | 4.15.0-1139.150 | |
linux-gcp-fips | 4.15.0-2085.91 |
Crucial Reboot & ABI Change Notice: Following the package update, a system reboot is mandatory to load the new, secure kernel into memory.
Furthermore, due to an unavoidable Application Binary Interface (ABI) change in this kernel update, all third-party kernel modules (e.g., proprietary drivers for graphics cards, VPNs, or storage arrays) must be recompiled and reinstalled against the new kernel headers.
For most users relying on standard Ubuntu meta-packages (e.g., linux-generic), this process is handled automatically during the upgrade. However, administrators who manually install out-of-tree drivers must perform this recompilation manually to ensure system stability.
Comprehensive List of Patched CVEs (Common Vulnerabilities and Exposures)
This security release addresses flaws documented in the following CVE identifiers. Each represents a unique weakness discovered and reported by security researchers worldwide.
CVE-2025-38350: A vulnerability in the media subsystem.
CVE-2025-37752: A flaw within the SPI subsystem.
CVE-2024-57996: A security issue in the USB core.
CVE-2024-53131 & CVE-2024-53130: Two related vulnerabilities in the NILFS2 filesystem.
CVE-2024-50202: A weakness in network traffic control.
CVE-2024-50051: An IPv6 networking flaw.
CVE-2024-47685: A separate issue in the media drivers.
CVE-2024-27074: A vulnerability patched in a previous general kernel update now included in this FIPS build.
CVE-2023-52477: An older vulnerability now mitigated.
Proactive Security: Extending Protection with Ubuntu Pro
While this patch addresses immediate threats, the long-term challenge lies in maintaining security for aging deployments. Ubuntu 18.04 LTS reached its standard end-of-life in May 2023, leaving systems without extended support exposed to future vulnerabilities.
This is where Ubuntu Pro provides immense value. It is a comprehensive subscription that extends security coverage for the entire Ubuntu universe of software—over 25,000 packages in Main and Universe repositories—for a full ten years.
For up to five machines, Ubuntu Pro is free of charge. It seamlessly provides automated security patches for critical infrastructure, dramatically reducing your organization's attack surface and compliance overhead. By enrolling your assets, you ensure they receive continuous vulnerability management long after the standard support period expires.
Get Ubuntu Pro for Free (Up to 5 Machines)
Frequently Asked Questions (FAQ)
Q: What is a FIPS-compliant kernel?
A: A FIPS (Federal Information Processing Standards) compliant kernel is a cryptographically validated version of the Linux kernel used by U.S. government agencies and contractors, as well as other regulated industries, to ensure encryption modules meet specific security requirements.
Q: Is a reboot absolutely necessary after applying this update?
A: Yes. Because the update replaces the core kernel binary that is only loaded into memory at boot time, a reboot is the only way to ensure the patched version is active and protecting your system.
Q: My system is behind a firewall; am I still at risk?
A: While firewalls mitigate remote attack vectors, several of these vulnerabilities (e.g., in USB drivers or the filesystem) could be exploited by an attacker with local user access, making internal systems potential targets.
Q: Where can I find more technical details on each CVE?
A: You can search for each CVE identifier (e.g., "CVE-2025-38350") on the National Vulnerability Database (NVD) or on the Ubuntu CVE Tracker.
Conclusion:
The USN-7755-2 update is a critical component of modern system hardening and cyber hygiene. Delaying the application of this patch unnecessarily increases organizational risk.
By promptly updating your kernels, managing third-party modules, and considering Ubuntu Pro for extended security maintenance, you take definitive steps to safeguard your infrastructure, protect sensitive data, and maintain compliance in an evolving threat landscape.
Nenhum comentário:
Postar um comentário