CVE-2025-38637

MEDIUM
Published Apr 18, 2025 Modified Nov 6, 2025 CWE-617

Description

In the Linux kernel, the following vulnerability has been resolved: net_sched: skbprio: Remove overly strict queue assertions In the current implementation, skbprio enqueue/dequeue contains an assertion that fails under certain conditions when SKBPRIO is used as a child qdisc under TBF with specific parameters. The failure occurs because TBF sometimes peeks at packets in the child qdisc without actually dequeuing them when tokens are unavailable. This peek operation creates a discrepancy between the parent and child qdisc queue length counters. When TBF later receives a high-priority packet, SKBPRIO's queue length may show a different value than what's reflected in its internal priority queue tracking, triggering the assertion. The fix removes this overly strict assertions in SKBPRIO, they are not necessary at all.

Is your site exposed to CVE-2025-38637?

Run a free security scan — no signup, results in seconds.

CVSS v3.1 Score

5.5
MEDIUM
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Weakness Type (CWE)

CWE-617 CWE-617

Affected Products

Vendor Product
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel
debian debian_linux

References

Frequently Asked Questions

What is CVE-2025-38637? +
In the Linux kernel, the following vulnerability has been resolved: net_sched: skbprio: Remove overly strict queue assertions In the current implementation, skbprio enqueue/dequeue contains an assertion that fails under certain conditions when SKBPRIO is used as a child qdisc under TBF with specific parameters. The failure occurs because TBF sometimes peeks at packets in the child qdisc without actually dequeuing them when tokens are unavailable. This peek operation creates a discrepancy between the parent and child qdisc queue length counters. When TBF later receives a high-priority packet, SKBPRIO's queue length may show a different value than what's reflected in its internal priority queue tracking, triggering the assertion. The fix removes this overly strict assertions in SKBPRIO, they are not necessary at all. It has a CVSS v3.1 base score of 5.5 (MEDIUM).
How severe is CVE-2025-38637? +
CVE-2025-38637 has a CVSS v3.1 score of 5.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.
What products are affected by CVE-2025-38637? +
CVE-2025-38637 affects products from debian, linux, specifically: debian_linux, linux_kernel. Check the affected products table above for specific version ranges.
How do I check if I'm vulnerable to CVE-2025-38637? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

Don't wait for an exploit

Scan your website for vulnerabilities like CVE-2025-38637 — free, no signup required.