CVE-2025-40074: ipv4: start using dst_dev_rcu()

highCVSS 7.1CVE-2025-40074

CSIRTS triage

product: Linux kernelOther

What: IPv4 routing code does not properly use dst_dev_rcu() for safe device reference counting.
Who is affected: Linux systems handling IPv4 routing are affected.
Urgency: High severity with CVSS 7.1; improper RCU handling in networking code can lead to use-after-free or data corruption.
Action: Apply Linux kernel patch CVE-2025-40074 to use dst_dev_rcu() correctly in IPv4 routing paths.

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 7.1
Published: 2026-08-06
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-40074

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-2025-400740.37% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 29% of all EPSS-scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2025-40074	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

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