high CVSS 7.1 EPSS <0.1%

CVE-2024-38621·Kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: media: stk1160: fix bounds checking in stk1160_copy_video() The subtract in this condition is reversed. The ->length is the length of the buffer. The ->bytesused is how many bytes we have copied thus far. When the condition is reversed that means the result of the subtraction is always negative but since it's unsigned then the result is a very high positive value. That means the overflow check is never true. Additionally, the ->bytesused doesn't actually work for this purpose because we're not writing to "buf->mem + buf->bytesused". Instead, the math to calculate the destination where we are writing is a bit involved. You calculate the number of full lines already written, multiply by two, skip a line if necessary so that we start on an odd numbered line, and add the offset into the line. To fix this buffer overflow, just take the actual destination where we are writing, if the offset is already out of bounds print an error and return. Otherwise, write up to buf->length bytes.

Severity
high
Software
Kernel
Fixed in
6.9.4
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-2024-38621 scores 7.1 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: 6.9.4

Fixed in: 6.9.4

How to fix this CVE

Update your Linux kernel to version 6.9.4 or later to remediate a buffer overflow vulnerability in the stk1160 video capture driver. This vulnerability allows local attackers with low privileges to cause a denial of service or potentially read sensitive kernel memory. Apply security patches immediately, especially if your system uses video capture hardware managed by the stk1160 driver.

sudo dnf update kernel kernel-devel

Defensia detects this vulnerability

How to check if you are affected

  1. Check your current kernel version: uname -r
  2. Verify if stk1160 driver is loaded: lsmod | grep stk1160
  3. List USB video devices: lsusb | grep -i video or dmesg | grep stk1160
  4. Confirm kernel version is 6.9.4 or later: uname -r | grep -E '6\.(9\.4|1[0-9]|[0-9]{2})'
  5. Review kernel logs for buffer-related errors: dmesg | grep -i 'stk1160\|buffer\|overflow' for the past 24 hours

FAQ

What is CVE-2024-38621?

CVE-2024-38621 is a buffer overflow vulnerability in the Linux kernel's stk1160 video capture driver where incorrect bounds checking logic allows writing beyond allocated buffer boundaries, enabling denial of service or memory disclosure attacks by local users.

Is CVE-2024-38621 being actively exploited?

No, this vulnerability is not currently listed as actively exploited in the CISA Known Exploited Vulnerabilities catalog, and no public exploit code is available.

What versions of Kernel are affected by CVE-2024-38621?

Linux kernel versions 6.7 through 6.9.3 are vulnerable. The fix was released in kernel 6.9.4.

How do I check if my server is vulnerable to CVE-2024-38621?

Run 'uname -r' and check if your kernel version is between 6.7 and 6.9.3. Then verify stk1160 driver presence with 'lsmod | grep stk1160'. If both conditions are true, your system is vulnerable.

Does Defensia detect CVE-2024-38621?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If Kernel is installed on a monitored server, CVE-2024-38621 will appear in your dashboard with remediation steps.

Related Kernel CVEs

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References

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