CVE-2024-46744·Kernel vulnerability
In the Linux kernel, the following vulnerability has been resolved: Squashfs: sanity check symbolic link size Syzkiller reports a "KMSAN: uninit-value in pick_link" bug. This is caused by an uninitialised page, which is ultimately caused by a corrupted symbolic link size read from disk. The reason why the corrupted symlink size causes an uninitialised page is due to the following sequence of events: 1. squashfs_read_inode() is called to read the symbolic link from disk. This assigns the corrupted value 3875536935 to inode->i_size. 2. Later squashfs_symlink_read_folio() is called, which assigns this corrupted value to the length variable, which being a signed int, overflows producing a negative number. 3. The following loop that fills in the page contents checks that the copied bytes is less than length, which being negative means the loop is skipped, producing an uninitialised page. This patch adds a sanity check which checks that the symbolic link size is not larger than expected. -- V2: fix spelling mistake.
- Severity
- high
- Software
- Kernel
- Fixed in
- 6.10.10
- Published
How likely is exploitation
FIRST's Exploit Prediction Scoring System puts the probability of this CVE being exploited in the next 30 days at <0.1% — higher than 2% of all published CVEs. EPSS is an independent forecast of exploitation, not a severity rating: it says nothing about how much damage a successful attack does, which is what a CVSS score measures.
Read the two together. CVE-2024-46744 scores 7.8 on CVSS, so a successful attack would be serious — but at <0.1%, almost nobody is currently attempting it. That is a different situation from a flaw under mass exploitation, and it is usually the difference between patching on your next maintenance window and patching tonight.
Affected versions
From: 6.7
Until: 6.10.10
Fixed in: 6.10.10
How to fix this CVE
Update your Linux kernel to version 6.10.10 or later to patch the Squashfs symbolic link validation vulnerability. This fix introduces proper sanity checks to prevent corrupted symlink metadata from causing memory corruption and system instability. Affected kernels 6.7 through 6.10.9 should be prioritized for immediate patching.
sudo dnf update kernel kernel-develDefensia detects this vulnerability
How to check if you are affected
- Step 1: Check installed kernel version with: uname -r (output should be 6.10.10 or later, or outside the 6.7-6.10.9 range)
- Step 2: Verify Squashfs is in use by checking mounted filesystems: mount | grep squashfs or lsmod | grep squashfs
- Step 3: Review kernel logs for KMSAN errors or memory initialization warnings: sudo dmesg | grep -i 'KMSAN\|uninit-value\|pick_link'
- Step 4: Confirm the patch is applied by checking kernel source or changelog: cat /proc/version or sudo apt-cache policy linux-image-generic
FAQ
What is CVE-2024-46744?
This vulnerability exists in the Linux Squashfs filesystem driver where corrupted symbolic link size metadata causes integer overflow and uninitialized memory to be exposed, leading to potential information disclosure or system instability.
Is CVE-2024-46744 being actively exploited?
No, this vulnerability is not listed on the CISA Known Exploited Vulnerabilities (KEV) catalog and no public exploits are currently available. Exploitation requires local access and disk-level filesystem corruption.
What versions of Kernel are affected by CVE-2024-46744?
Linux kernel versions 6.7 through 6.10.9 are vulnerable. Version 6.10.10 and later contain the fix. Users on older LTS kernels (6.1.x, 6.6.x) should verify their distribution's backport status.
How do I check if my server is vulnerable to CVE-2024-46744?
Run: uname -r | grep -E '^6\.(7|8|9|10\.[0-9]($|[^0-9]))' — if this matches, your kernel is vulnerable. Cross-reference with your distribution's kernel package version.
Does Defensia detect CVE-2024-46744?
Yes — Defensia's CVE advisory scanner compares installed kernel package versions against the NVD database. If a vulnerable kernel version (6.7-6.10.9) is detected on a monitored system, CVE-2024-46744 will appear in your dashboard with remediation steps.
Related Kernel CVEs
References
- https://git.kernel.org/stable/c/087f25b2d36adae19951114ffcbb7106ed405ebb
- https://git.kernel.org/stable/c/1b9451ba6f21478a75288ea3e3fca4be35e2a438
- https://git.kernel.org/stable/c/5c8906de98d0d7ad42ff3edf2cb6cd7e0ea658c4
- https://git.kernel.org/stable/c/810ee43d9cd245d138a2733d87a24858a23f577d
- https://git.kernel.org/stable/c/c3af7e460a526007e4bed1ce3623274a1a6afe5e
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