CVE-2026-63919
Linux kernel xfrm netns lifetime bug allows kernel memory corruption and crashes.
Is CVE-2026-63919 being exploited?
Not confirmed. CVE-2026-63919 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.65% probability of exploitation in the next 30 days.
How severe is CVE-2026-63919?
CVE-2026-63919 is rated High. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-63919?
Yes. A fix has been recorded for CVE-2026-63919. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-63919 affect?
CVE-2026-63919 affects Linux kernel (xfrm subsystem), Distributions using affected kernel versions, Systems using IPsec/transport-mode. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-63919?
Apply vendor kernel updates or backported xfrm fixes immediately
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Stale netns pointer in xfrm transport reinjection can cause kernel memory corruption, crashes (DoS) and may enable local or network-triggered privilege escalation or code execution via crafted IPsec packets.
Patch when possible
- affected>= 7b3801927e52f8621de311277f7fc727635019e7 and < 7ee59eda8820b758ed29e1cd3222359c7b97302c
- affected>= 7b3801927e52f8621de311277f7fc727635019e7 and < 2df7059a18afb7d3aee6c36cad5d371c198111d4
- affected>= 7b3801927e52f8621de311277f7fc727635019e7 and < 8dfabcba6a943a7a02ebe1e1637c361ba96acbaa
- affected>= 7b3801927e52f8621de311277f7fc727635019e7 and < 48ce101cd630d6745b6923b5bad8358bc4c119da
- affected>= 7b3801927e52f8621de311277f7fc727635019e7 and < 55ddfc41451f01c588089cd74957a05311b6f202
- affected>= 7b3801927e52f8621de311277f7fc727635019e7 and < 9f7ebb45a83afc3216e855e57d51bb4bc9b5232e
- affected>= 7b3801927e52f8621de311277f7fc727635019e7 and < 9f67a36e91bb50d358760f381f233913fe5c09f8
- affected>= 7b3801927e52f8621de311277f7fc727635019e7 and < c16f74dc1d75d0e2e7670076d5375deda110ebeb
- affected5.6
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.