CVE-2026-74577: net: mpls: initialize rtm_tos in mpls_getroute()

lowCVSS 3.3CVE-2026-74577

CSIRTS triage

vendor: Linux product: Linux kernel Information disclosure

What: MPLS route lookup does not initialize the rtm_tos field, leaking uninitialized kernel memory.
Who is affected: Systems running Linux kernel with MPLS routing enabled.
Urgency: Low priority; minor information disclosure of kernel memory, not exploited.
Action: Apply kernel patch to initialize rtm_tos field in mpls_getroute().

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: low — CVSS 3.3
Published: 2026-08-11
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-74577

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-2026-745770.17% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 6% of all EPSS-scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-74577	coverage & exploitation status	NVD · CVE.org

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unknownCVE-2026-74577: In the Linux kernel, the following vulnerability has been resolved: net: mpls: initialize rtm_…nvd

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