CVE-2026-68138: net/sched: serialize qdisc_rtab_list against concurrent get/put

highpublic exploitCVSS 7.1CVE-2026-68138

CSIRTS triage

vendor: Linux product: Linux kernelOther

What: The qdisc_rtab_list in net/sched lacks serialization for concurrent get/put operations, causing race conditions.
Who is affected: Linux systems with active queueing discipline configuration and concurrent traffic control operations.
Urgency: High; CVSS 7.1 indicates significant risk and should be patched promptly.
Action: Apply Linux kernel patch serializing qdisc_rtab_list access.

AI-assisted analysis generated from the source advisory — verify against the original.

⚡ Watch Linux kernel

Get an email when a new Linux kernel advisory drops — max one per day, one-click unsubscribe.

Details

Source: Microsoft Security Response Center (INTL · vendor-psirt · site)
Severity: high — CVSS 7.1
Published: 2026-08-11
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-68138

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-681380.28% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 20% of all EPSS-scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-68138	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

high[NEW] [high] Linux Kernel: Multiple vulnerabilitiescert-bund
unknownDSA-6466-1 linux - security updatedebian
highCVE-2026-68138: In the Linux kernel, the following vulnerability has been resolved: net/sched: serialize qdisc…nvd

Recent advisories for net/sched

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

highCVE-2026-74704: In the Linux kernel, the following vulnerability has been resolved: net/sched: sch_cake: drop …nvd · 2026-08-22
highCVE-2026-74700: In the Linux kernel, the following vulnerability has been resolved: net/sched: cls_api: Always…nvd · 2026-08-22
highCVE-2026-74663: In the Linux kernel, the following vulnerability has been resolved: net/sched: reject overly d…nvd · 2026-08-22
highCVE-2026-74621: In the Linux kernel, the following vulnerability has been resolved: net/sched: act_ct: fix sk_…nvd · 2026-08-22
unknownCVE-2026-74620: In the Linux kernel, the following vulnerability has been resolved: net/sched: act_gact, act_p…nvd · 2026-08-22
highCVE-2026-74583: In the Linux kernel, the following vulnerability has been resolved: net/sched: cls_route: fix …nvd · 2026-08-21