CVE-2026-45940: net: stmmac: fix oops when split header is enabled

highCVSS 7CVE-2026-45940

CSIRTS triage

vendor: Linux product: Linux kernel Memory corruption

What: A null pointer dereference or memory corruption occurs in the stmmac network driver when split header mode is enabled.
Who is affected: Systems running Linux kernel with stmmac Ethernet driver and split header feature enabled.
Urgency: High severity (CVSS 7.0) with potential for denial of service or system crash; not currently exploited.
Action: Apply Linux kernel patch fixing stmmac split header handling or disable split header mode.

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

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Details

Source: Microsoft Security Response Center (INTL · vendor-psirt · site)
Severity: high — CVSS 7
Published: 2026-08-06
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-45940

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-2026-459400.16% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 5% of all EPSS-scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-45940	coverage & exploitation status	NVD · CVE.org

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