CVE-2024-42311
📋 TL;DR
This CVE describes an uninitialized memory vulnerability in the Linux kernel's HFS filesystem driver. When creating HFS inodes, certain fields in the hfs_inode_info structure are not properly initialized, potentially exposing kernel memory contents. This affects systems using the HFS filesystem driver, which is less common than other filesystems but still present in many Linux distributions.
💻 Affected Systems
- Linux kernel
📦 What is this software?
Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →⚠️ Risk & Real-World Impact
Worst Case
Kernel memory disclosure could leak sensitive information including cryptographic keys, process memory, or other privileged data to unprivileged users, potentially enabling further exploitation.
Likely Case
Information disclosure of uninitialized kernel memory, which could contain fragments of sensitive data or be used to infer kernel memory layout for other attacks.
If Mitigated
Limited impact if HFS filesystem is not mounted or used, or if access controls prevent unprivileged users from mounting filesystems.
🎯 Exploit Status
Exploitation requires local access and ability to mount/create HFS filesystems. The vulnerability was discovered through fuzzing (syzbot).
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Multiple stable kernel versions with fixes: 10f7163bfb5f8b4e0c9c05a939f20b8540e33c65 and others
Vendor Advisory: https://git.kernel.org/stable/c/10f7163bfb5f8b4e0c9c05a939f20b8540e33c65
Restart Required: Yes
Instructions:
1. Update Linux kernel to patched version from your distribution's repositories. 2. Reboot system to load new kernel. 3. Verify kernel version after reboot.
🔧 Temporary Workarounds
Disable HFS filesystem support
linuxPrevent loading of HFS filesystem driver to eliminate attack surface
echo 'install hfs /bin/false' >> /etc/modprobe.d/disable-hfs.conf
echo 'blacklist hfs' >> /etc/modprobe.d/disable-hfs.conf
update-initramfs -u
Prevent HFS mounting
linuxUse mount restrictions to prevent HFS filesystem mounting
echo 'nodev' >> /etc/fstab for HFS partitions
Use mount namespaces to restrict filesystem access
🧯 If You Can't Patch
- Restrict user permissions to prevent mounting filesystems
- Implement mandatory access controls (SELinux/AppArmor) to limit filesystem operations
🔍 How to Verify
Check if Vulnerable:
Check if HFS module is loaded: lsmod | grep hfs. Check kernel version against patched versions.Check Version:
uname -rVerify Fix Applied:
Verify kernel version is updated to patched version and HFS module is either not loaded or from patched kernel.📡 Detection & Monitoring
Log Indicators:
- Kernel logs showing HFS filesystem mounting
- System calls related to mount operations on HFS
Network Indicators:
- Not applicable - local vulnerability
SIEM Query:
process.name="mount" AND command_line LIKE "*hfs*" OR filesystem.type="hfs"🔗 References
- https://git.kernel.org/stable/c/10f7163bfb5f8b4e0c9c05a939f20b8540e33c65
- https://git.kernel.org/stable/c/26a2ed107929a855155429b11e1293b83e6b2a8b
- https://git.kernel.org/stable/c/4a52861cd76e79f1a593beb23d096523eb9732c2
- https://git.kernel.org/stable/c/58d83fc160505a7009c39dec64effaac5129b971
- https://git.kernel.org/stable/c/9c4e40b9b731220f9464975e49da75496e3865c4
- https://git.kernel.org/stable/c/d3493d6f0dfb1ab5225b62faa77732983f2187a1
- https://git.kernel.org/stable/c/d55aae5c1730d6b70d5d8eaff00113cd34772ea3
- https://git.kernel.org/stable/c/f7316b2b2f11cf0c6de917beee8d3de728be24db
- https://lists.debian.org/debian-lts-announce/2024/10/msg00003.html
- https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html
