How severe is CVE-2025-38637?

CVE-2025-38637 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2025-38637 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (15th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-38637?

CVE-2025-38637 primarily affects Linux Linux Kernel. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2025-38637?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2025-38637 have an EU (EUVD) identifier?

Yes. CVE-2025-38637 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-11821.

When was CVE-2025-38637 published?

CVE-2025-38637 was published on 2025-04-18 and last updated on 2026-06-17.

CVE-2025-38637

CVE-2025-38637 is a medium-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-617.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
EPSS exploit prediction: 0% (15th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-11821
Weakness: CWE-617
Affected product: Linux Linux Kernel
Published: 2025-04-18
Last modified: 2026-06-17

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.

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.
How severe is CVE-2025-38637?: CVE-2025-38637 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2025-38637 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (15th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-38637?: CVE-2025-38637 primarily affects Linux Linux Kernel. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-38637?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-38637 have an EU (EUVD) identifier?: Yes. CVE-2025-38637 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-11821.
When was CVE-2025-38637 published?: CVE-2025-38637 was published on 2025-04-18 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*

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