CVE-2026-64189 Linux vulnerability
In the Linux kernel, the following vulnerability has been resolved: netfilter: ipset: fix race between dump and ip_set_list resize The release path of ip_set_dump_do() and ip_set_dump_done() read inst->ip_set_list via ip_set_ref_netlink(), a plain rcu_dereference_raw() of the array pointer. These run from netlink_recvmsg() without the nfnl mutex and without an RCU read-side critical section. A concurrent ip_set_create() can grow the array: it publishes the new array, calls synchronize_net() and then kvfree()s the old one. Since the dump paths read the array outside any RCU reader, synchronize_net() does not wait for them and the old array can be freed while they still index into it, causing a use-after-free. The dumped set itself stays pinned via set->ref_netlink, so only the array load needs protecting. Take rcu_read_lock() around it, matching ip_set_get_byname() and __ip_set_put_byindex(). BUG: KASAN: slab-use-after-free in ip_set_dump_do (net/netfilter/ipset/ip_set_core.c:1697) Read of size 8 at addr ffff88800b5c4018 by task exploit/150 Call Trace: ... kasan_report (mm/kasan/report.c:595) ip_set_dump_do (net/netfilter/ipset/ip_set_core.c:1697) netlink_dump (net/netlink/af_netlink.c:2325) netlink_recvmsg (net/netlink/af_netlink.c:1976) sock_recvmsg (net/socket.c:1159) __sys_recvfrom (net/socket.c:2315) ... Oops: general protection fault, probably for non-canonical address ... KASAN NOPTI KASAN: maybe wild-memory-access in range [0x02d6...d0-0x02d6...d7] RIP: 0010:ip_set_dump_do (net/netfilter/ipset/ip_set_core.c:1698) Kernel panic - not syncing: Fatal exception
Browse Linux security risksQuick answer
Linux should be reviewed and updated if it matches the affected versions. The recommended fix is to apply the vendor-supported patched version or the mitigation steps below, then retest the public website with Fixnx.
Who is affected
Affected versions
- < ff86ea9b7fdf70564e60436fbee68c96bc459943
- < 81d54c766337b923eec26da0a13406760b091093
- < e8ee198bbc04a32d336e79160fde980e0235b39f
- < 7cd9103283b26b917360ec99d7d2f2d761bcf1ab
- 2f6bf7917f55f9dae913193e49672b3598620eab
- < 4.20
- 4.20
Fixed versions
- 6.12.96
- 6.18.39
- 7.1.4
- 7.2-rc2
How to fix it
CVE-2026-64189 affects Linux and involves memory-safety failure. A crafted input may corrupt memory, crash the process, or enable code execution in the affected context. Prioritize deployments that process untrusted input, expose the affected feature, or hold sensitive data. Upgrade Linux to 6.12.96, 6.18.39, 7.1.4, 7.2-rc2 or a later vendor-supported fixed release.
- Inventory every deployment, device, package, plugin, container, build, and environment that uses Linux.
- Compare the installed version with the recorded affected range: < ff86ea9b7fdf70564e60436fbee68c96bc459943, < 81d54c766337b923eec26da0a13406760b091093, < e8ee198bbc04a32d336e79160fde980e0235b39f, < 7cd9103283b26b917360ec99d7d2f2d761bcf1ab, 2f6bf7917f55f9dae913193e49672b3598620eab, < 4.20.
- Upgrade Linux to 6.12.96, 6.18.39, 7.1.4, 7.2-rc2 or a later vendor-supported fixed release.
- Until patched, limit untrusted files and peers, apply resource limits, and isolate the affected parser or service.
- Review configuration, roles, tokens, network paths, and exposed endpoints connected to Linux; remove access that is not required.
- Review application, system, proxy, and audit logs for requests and behavior linked to the affected feature and CVE.
- If exploitation is suspected, isolate affected assets, preserve evidence, rotate exposed credentials or keys, restore trusted data, and rebuild compromised systems before returning them to service.
Scan now. Google sign-in is only needed to unlock fix guidance.
Verify the fix
- Confirm every affected asset now runs the fixed vendor-supported release or has the documented mitigation for CVE-2026-64189 in place.
- Use a safe regression test to confirm the affected memory-safety failure path no longer produces the vulnerable behavior.
- Confirm temporary access controls, endpoint restrictions, network blocks, and least-privilege settings remain effective after the update.
- Review post-remediation logs and rerun Fixnx plus the relevant package, dependency, firmware, browser, or product-specific security check.
- Document affected assets, versions, changes, validation evidence, reviewed logs, and any credential rotation, cleanup, or replacement completed.
Related categories
Related security risks
More published guidance from the same primary category.
Trusted references
FAQ
What is affected by CVE-2026-64189?
Linux versions listed as affected should be reviewed: < ff86ea9b7fdf70564e60436fbee68c96bc459943, < 81d54c766337b923eec26da0a13406760b091093, < e8ee198bbc04a32d336e79160fde980e0235b39f, < 7cd9103283b26b917360ec99d7d2f2d761bcf1ab, 2f6bf7917f55f9dae913193e49672b3598620eab, < 4.20, 4.20.
What should I fix first?
Start with internet-facing sites, admin panels, login flows, plugins, themes, modules, packages, and systems that process user-controlled input or sensitive data.
How do I confirm the fix worked?
Apply the patched version or mitigation, clear caches where relevant, retest the affected workflow, and run a new Fixnx scan to verify public website exposure signals.
How are Fixnx security risk categories chosen?
Fixnx keeps one canonical risk page and assigns only broad, relevant categories such as ecosystem, technology area, or vulnerability class.