CVE-2025-38637

net_sched: skbprio: Remove overly strict queue assertions

Published Apr 18, 2025 CVSS 3.1 · 5.5 Medium EPSS < 1% KEV · Not listed
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

Sign in to view the affected projects.

Advisories

Source ID Title
Debian DLA Debian DLA DLA-4178-1 linux security update
Debian DLA Debian DLA DLA-4193-1 linux-6.1 security update
Debian DSA Debian DSA DSA-5907-1 linux security update
EUVD EUVD EUVD-2025-11821 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.
Ubuntu USN Ubuntu USN USN-7585-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7585-2 Linux kernel (FIPS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7585-3 Linux kernel (FIPS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7585-4 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-7585-5 Linux kernel (HWE) vulnerabilities
Ubuntu USN Ubuntu USN USN-7585-6 Linux kernel (BlueField) vulnerabilities
Ubuntu USN Ubuntu USN USN-7585-7 Linux kernel (Raspberry Pi) vulnerabilities
Ubuntu USN Ubuntu USN USN-7591-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7591-2 Linux kernel (FIPS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7591-3 Linux kernel (Real-time) vulnerabilities
Ubuntu USN Ubuntu USN USN-7591-4 Linux kernel (AWS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7591-5 Linux kernel (Intel IoTG) vulnerabilities
Ubuntu USN Ubuntu USN USN-7591-6 Linux kernel (Raspberry Pi) vulnerabilities
Ubuntu USN Ubuntu USN USN-7592-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7593-1 Linux kernel (HWE) vulnerabilities
Ubuntu USN Ubuntu USN USN-7594-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7594-2 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-7594-3 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7597-1 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-7597-2 Linux kernel (Azure FIPS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7598-1 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-7602-1 Linux kernel (Xilinx ZynqMP) vulnerabilities
Ubuntu USN Ubuntu USN USN-7605-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7605-2 Linux kernel (Low Latency) vulnerabilities
Ubuntu USN Ubuntu USN USN-7606-1 Linux kernel (OEM) vulnerabilities
Ubuntu USN Ubuntu USN USN-7628-1 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-7640-1 Linux kernel (IoT) vulnerabilities
Ubuntu USN Ubuntu USN USN-7655-1 Linux kernel (Intel IoTG) vulnerabilities
Ubuntu USN Ubuntu USN USN-7835-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7835-2 Linux kernel (Real-time) vulnerabilities
Ubuntu USN Ubuntu USN USN-7835-3 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7835-4 Linux kernel (HWE) vulnerabilities
Ubuntu USN Ubuntu USN USN-7835-5 Linux kernel (Oracle) vulnerabilities
Ubuntu USN Ubuntu USN USN-7835-6 Linux kernel (AWS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7887-1 Linux kernel (Raspberry Pi Real-time) vulnerabilities
Ubuntu USN Ubuntu USN USN-7887-2 Linux kernel (Raspberry Pi) vulnerabilities
Ubuntu USN Ubuntu USN USN-7940-1 Linux kernel (Azure FIPS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7940-2 Linux kernel (Azure, N-Series) vulnerabilities
History
Type Values Removed Values Added
First Time appeared Debian
Debian debian Linux
CPEs cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Debian
Debian debian Linux
Type Values Removed Values Added
Weaknesses CWE-617
Type Values Removed Values Added
References
Metrics threat_severity

None

cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

threat_severity

Moderate

Type Values Removed Values Added
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.
Title net_sched: skbprio: Remove overly strict queue assertions
References
Weaknesses

Sources

Status
PUBLISHED
Assigner
Linux
Published
Updated
May 11, 2026, 9:32 PM
Reserved
Apr 16, 2025, 4:51 AM
Status
Analyzed
Published
Apr 18, 2025, 7:15 AM
Modified
Jun 17, 2026, 9:17 AM
Severity
Moderate
Public date
Apr 18, 2025, 12:00 AM