Affects the Linux kernel TCP stack, widely deployed across servers, cloud, network appliances and endpoints; enables network-level spoofing/hijack scenarios impacting many organizations.
CVE-2026-64024
Linux kernel TCP ISN leak allows predictable initial sequence numbers.
Is CVE-2026-64024 being exploited?
Not confirmed. CVE-2026-64024 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 0.39% probability of exploitation in the next 30 days.
How severe is CVE-2026-64024?
CVE-2026-64024 is rated Critical with a CVSS score of 9.4. 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-2026-64024?
Yes. A fix has been recorded for CVE-2026-64024. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-64024 affect?
CVE-2026-64024 affects Linux kernel (tcp_v4/tcp_v6), Linux servers and desktops, Containers/VMs on Linux hosts, Network appliances running Linux, and 1 further product or version. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-64024?
Apply vendor kernel updates and reboot affected systems; restrict TCP exposure until patched.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Predictable TCP ISNs let attackers spoof or hijack TCP connections, inject packets, or bypass connection validation on affected Linux hosts.
Immediate action required
- affected>= 41eecbd712b73f0d5dcf1152b9a1c27b1f238028 and < e47f7060eaf60894e3e4d0e3c4fe6e1f2eacfbdd
- affected>= 41eecbd712b73f0d5dcf1152b9a1c27b1f238028 and < 4affe063fa56c880cbea8d0bfded0bb80751579d
- affected>= 41eecbd712b73f0d5dcf1152b9a1c27b1f238028 and < 1bbf0ced1d9db73ac7893c2187f3459288603e0d
- affected6.10
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.