CVE-2024-38621: In the Linux kernel, the following vulnerability has been resolved: media: stk1160: fix bounds checking in stk1160_copy_video() The subtract in this...

Description

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.

Metrics

CVSS 3.1

7.1/10

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H

EPSS Probability

0.27%

18.4th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-787

Affected Software

Vendor	Product	Versions
Linux	Linux Kernel	>= 3.7, < 4.19.316
Linux	Linux Kernel	>= 4.20, < 5.4.278
Linux	Linux Kernel	>= 5.5, < 5.10.219
Linux	Linux Kernel	>= 5.11, < 5.15.161
Linux	Linux Kernel	>= 5.16, < 6.1.93
Linux	Linux Kernel	>= 6.2, < 6.6.33
Linux	Linux Kernel	>= 6.7, < 6.9.4

References

Timeline

Published: Jun 21, 2024
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2024-38621?

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.

How severe is CVE-2024-38621?

CVE-2024-38621 has a CVSS score of 7.1/10 (HIGH severity). The EPSS model estimates a 0.27% probability of exploitation in the next 30 days.

How do I fix CVE-2024-38621?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.