CVE-2025-38115

Published Jul 3, 2025

Last updated 8 days ago

CVSS high 7.8

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: net_sched: sch_sfq: fix a potential crash on gso_skb handling SFQ has an assumption of always being able to queue at least one packet. However, after the blamed commit, sch->q.len can be inflated by packets in sch->gso_skb, and an enqueue() on an empty SFQ qdisc can be followed by an immediate drop. Fix sfq_drop() to properly clear q->tail in this situation. ip netns add lb ip link add dev to-lb type veth peer name in-lb netns lb ethtool -K to-lb tso off # force qdisc to requeue gso_skb ip netns exec lb ethtool -K in-lb gro on # enable NAPI ip link set dev to-lb up ip -netns lb link set dev in-lb up ip addr add dev to-lb 192.168.20.1/24 ip -netns lb addr add dev in-lb 192.168.20.2/24 tc qdisc replace dev to-lb root sfq limit 100 ip netns exec lb netserver netperf -H 192.168.20.2 -l 100 & netperf -H 192.168.20.2 -l 100 & netperf -H 192.168.20.2 -l 100 & netperf -H 192.168.20.2 -l 100 &
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Modified
Products
linux_kernel, debian_linux

Risk scores

CVSS 3.1

Type
Primary
Base score
5.5
Impact score
3.6
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Severity
MEDIUM

Weaknesses

nvd@nist.gov
CWE-401

Social media

Hype score
Not currently trending

  1. CVE-2025-38115 In the Linux kernel, the following vulnerability has been resolved: net_sched: sch_sfq: fix a potential crash on gso_skb handling SFQ has an assumption of always be… https://t.co/yZcpMvuSla

    @CVEnew

    3 Jul 2025

    255 Impressions

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    0 Replies

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Configurations

Related CVEs

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References

Sources include official advisories and independent security research.