Comparing KernelCare to
Oracle Ksplice

Oracle helped pioneer rebootless Linux patching. Ksplice has been applying kernel fixes to running servers long before most vendors shipped anything comparable. The technology works. The real question is what it costs you to use it.

Ksplice is not a standalone product. It is a feature of Oracle Linux Premier Support, so rebootless patching arrives bundled with a costly Oracle support subscription and, increasingly, with Oracle’s kernel. It live-patches only a selection of even the Critical and Important vulnerabilities, fixes critical userspace libraries only after a one-time restart that takes much of the stack offline, and forces systems to use Oracle’s kernel before it will patch them. The result is live patching that leaves gaps, forces downtime, and steadily pulls your estate toward Oracle.

TuxCare’s KernelCare was built to avoid that. It patches all kernel and critical userspace vulnerabilities in place, on whatever distribution a system already runs, for $50 per system per year. The comparison below breaks down where the two diverge.

	Oracle Ksplice	KernelCare
Supported distributions	Oracle Linux (UEK / Red Hat Compatible Kernels) & Ubuntu; RHEL kernels are not supported	Oracle Linux 6 – 10, Ubuntu, Debian, RHEL, AlmaLinux, Rocky, and many others
Vulnerabilities patched	🟡 Selected Important and Critical CVEs	✅ All CVEs, regardless of severity
Supported architectures	x86-64, arm64	x86-64, arm64
Coverage for critical userspace (OpenSSL, glibc)	🟡 Yes, but only for Ksplice-aware builds on Oracle Linux (not Ubuntu), and with a one-time restart	✅ Yes
Kernel patching lifetime	🟡 Ends when kernel drops off the maintained list or Premier Support lapses	✅ Practically unlimited
Live patching for end-of-life OS	🟡 Only via Oracle Linux Extended Support paid add-on, with coverage limited to critical errata only	✅ Oracle Linux 6, 7, plus Ubuntu, RHEL, AlmaLinux, and many others
Rebootless roll-back functionality	✅ Yes	✅ Yes
Centralized air-gapped management	❌ Self-hosted option is no longer supported	✅ Included (ePortal)
API available	✅ Yes	✅ Yes
Custom patch delivery	❌ Not available	✅ Fully managed
Add-ons	–	LibCare, custom patches
Cost	Oracle Linux Premier Support: $1,399/CPU pair/yr (Premier Plus $2,499)	From $50/system/yr; bulk pricing available

The chart shows where the two diverge. The rest of this comparison unpacks what each difference means for the systems you actually run.

Few estates run just one distribution, so the first thing to ask of a patching tool is how much of the mix it can cover. Under Premier Support, Ksplice maintains Oracle’s UEK and RHCK kernels, as well as Ubuntu. Critically, Oracle no longer maintains Ksplice patches for the RHEL kernel, so RHEL itself falls outside the set it covers.

KernelCare takes the opposite stance. It live-patches 70+ distro versions out of the box — RHEL, AlmaLinux, Rocky Linux, Ubuntu, Debian, Oracle Linux, Amazon Linux, CloudLinux, and many others — so a single tool and workflow cover a mixed estate.

The whole point of live patching is to fix vulnerabilities quickly, so the first question is which ones a tool actually fixes. According to our own research, Ksplice patches only a selection of even the Critical and Important CVEs. Oracle also assigns its own severity ratings, which can be lower than the score a CVE receives in the National Vulnerability Database. Those ratings assume standard configurations, so a flaw Oracle deprioritizes can still be a real exposure in certain setups. With no live patch coming, the fix will wait until the next kernel update and a reboot.

KernelCare removes the guesswork by live-patching all kernel CVEs, regardless of severity rating, so your coverage does not hinge on how a given CVE is scored.

Live patching should keep the whole system secure without restarts, but most tools never touch critical OpenSSL and glibc libraries. Ksplice does offer critical userspace patching, but only for Ksplice-aware library builds that still require a one-time restart. Because these libraries sit underneath almost everything you run, that restart can mean taking down much of your stack.

KernelCare closes this gap with LibCare, patching OpenSSL and glibc shared libraries in memory across supported distributions, without restarting the applications that depend on them. Patching critical userspace without downtime enables teams to meet PCI DSS and FedRAMP remediation deadlines and satisfy SOC 2 and HIPAA security requirements on systems that cannot be taken offline.

With Ksplice, patching lasts while the kernel remains on Oracle’s maintained list and your Premier subscription is active. The moment either lapses, when the kernel drops off the list or the subscription ends, you have to run yum update and reboot to keep receiving fixes.

KernelCare puts no expiry clock on patching. It patches a loaded kernel for as long as you keep running it, without a forced reboot to stay covered.

Workloads routinely outlive their distribution’s support window. Once it closes, vendor security updates stop, and these are often the systems you can least afford to reboot or rebuild, which is why live patching matters most. Ksplice keeps patching a release past that window only if you buy Oracle Linux Extended Support, which narrows coverage to critical errata, lasts only a few more years, and applies only to Oracle Linux.

KernelCare, by contrast, continues to deliver live patches for end-of-life distributions such as Oracle Linux 6 and 7, so the systems you cannot retire on schedule remain protected while you plan the move on your own timeline.

At any real scale, live patching has to be managed centrally, increasingly in networks with no internet access. Both Ksplice and KernelCare can get patches into an isolated network. The difference is management. With Ksplice, the self-hosted product that centralizes it, Oracle Linux Manager, is no longer supported, and its replacement, OS Management Hub, must stay connected to Oracle’s cloud. In a true air gap, you are left maintaining local mirrors and Offline clients manually.

KernelCare includes ePortal, a self-hosted patch server that runs inside the isolated network at no extra license cost. It gives you feeds, staged rollouts, controlled deployment, and inventory locally, so the management layer lives inside the air gap rather than in a vendor cloud.

Some environments need a fix the vendor has not shipped, or a patch tailored to their own configuration. Ksplice offers no custom patches at all. Its catalog is limited to what Oracle ships for Oracle Linux components, so anything outside that set is simply unavailable.

KernelCare offers fully managed custom patches that TuxCare engineers build, test, and maintain for you, including special versions and non-standard configurations. You get the fix you need without taking on the work and risk of authoring live patches in-house.

KernelCare starts at $50 per system per year for kernel live patching and runs on your existing OS with no Oracle subscription and kernel migration required. Userspace live patching for OpenSSL and glibc is available through the LibCare add-on. Ksplice, by contrast, carries no separate fee but rides on Oracle Linux Premier Support, which is listed at $1,399 per CPU pair per year (Premier Plus: $2,499).

The gap is starkest at fleet scale. Full rebootless coverage for 100 systems is about $5,000 a year with KernelCare. The same fleet on Oracle Linux Premier Support lists at roughly $139,900 a year – about 28 times more – before counting the engineering cost of migrating non-Oracle systems onto Oracle’s kernel.

If your estate is already all-in on Oracle Linux Premier Support, Ksplice is right there in the bundle, and it can seem like the natural choice. The point of this comparison is what that bundle asks of everyone else:

• It live-patches only a selection of even the Critical and Important vulnerabilities, leaving the rest for the next kernel update and a reboot.
• RHEL and other systems have to migrate to Oracle’s kernel.
• Userspace patching requires Ksplice-aware library builds and is gated to Oracle Linux.
• Coverage lasts only while you keep an active Premier subscription.
• Every part of it pulls you deeper into Oracle’s stack.

KernelCare was built to remove those trade-offs. It continuously patches the kernel and userspace, regardless of severity and well past end of life, with fully managed custom patches and air-gapped management included, for a fraction of a Premier entitlement. So, whether you run a mixed estate, an RHEL fleet you would rather not migrate to Oracle’s kernel, or simply want to avoid deeper Oracle lock-in, KernelCare is the broader, simpler, and far more economical choice.

Moving to KernelCare is straightforward and requires no OS migration. A single quick-start script installs the agent, and your systems begin receiving continuous live patching across kernel and critical userspace.

For teams that want to see it first, KernelCare offers a 30-day free trial with full functionality, so you can confirm uninterrupted coverage before committing.