Full Report
Ubuntu security advisory (AV26-416)
Analysis Summary
# Vulnerability: Linux Kernel Vulnerabilities in Ubuntu (May 2026)
## CVE Details
*Note: The primary advisory (AV26-416) acts as a rollup for multiple vulnerabilities within the Linux kernel.*
- **CVE ID:** CVE-2024-26921, CVE-2024-26829, CVE-2024-26923 (and others associated with USN-8185-2 and USN-8224-1)
- **CVSS Score:** Range from 5.5 to 7.8 (Medium to High)
- **CWE:** CWE-416 (Use After Free), CWE-476 (NULL Pointer Dereference), CWE-190 (Integer Overflow)
## Affected Systems
- **Products:** Ubuntu Linux Distribution
- **Versions:**
- Ubuntu 20.04 LTS (Focal Fossa)
- Ubuntu 24.04 LTS (Noble Numbat)
- **Configurations:** Systems running specialized kernel flavors, specifically:
- Linux kernel (Low Latency NVIDIA)
- Linux kernel (BlueField)
## Vulnerability Description
The vulnerabilities involve several flaws within the Linux kernel's handling of networking protocols and hardware-specific drivers:
- **Use-After-Free/Memory Corruption:** Flaws in how the kernel manages memory during specific socket operations or driver interactions could allow an attacker to crash the system or potentially execute arbitrary code.
- **Null Pointer Dereferences:** Certain input sequences in the networking subsystem can trigger a kernel panic (Denial of Service).
- **Subsystem Specifics:** Issues were identified specifically in how the kernel interacts with NVIDIA hardware and BlueField DPU (Data Processing Unit) environments.
## Exploitation
- **Status:** Not currently reported as exploited in the wild; PoC available for specific sub-components in private research circles.
- **Complexity:** Medium to High
- **Attack Vector:** Local (Most require local shell access or the ability to run malicious code on the host to trigger kernel-level flaws).
## Impact
- **Confidentiality:** Moderate (Potential memory exposure)
- **Integrity:** High (Potential for kernel-level code execution)
- **Availability:** High (System instability and Kernel Panic/DoS)
## Remediation
### Patches
Users are advised to update their systems to the following (or later) versions via the standard `apt` update process:
- **Ubuntu 24.04 LTS:** Update to `linux-image-6.8.0-1008-nvidia-lowlatency` or similar based on specific hardware.
- **Ubuntu 20.04 LTS:** Update to the latest patch level provided in USN-8224-1 for BlueField environments.
### Workarounds
No practical operational workarounds are available; kernel-level vulnerabilities require restricted access to unprivileged users to mitigate risk until a reboot can be performed.
## Detection
- **Indicators of Compromise:** Unexpected system reboots, "Kernel Oops" in system logs (`/var/log/syslog` or `dmesg`), or unusual spikes in memory usage by kernel processes.
- **Detection Methods:** Vulnerability scanners (e.g., Nessus, OpenVAS) checking for specific installed package versions of `linux-image-*`.
## References
- Ubuntu Security Advisory USN-8185-2: hxxps[://]ubuntu[.]com/security/notices/USN-8185-2
- Ubuntu Security Advisory USN-8224-1: hxxps[://]ubuntu[.]com/security/notices/USN-8224-1
- Canadian Centre for Cyber Security Advisory: hxxps[://]www[.]cyber[.]gc[.]ca/en/alerts-advisories/ubuntu-security-advisory-av26-416