KVM
Hacker ApprovedRanked 3 of 16 hypervisors by recommenders
Free Linux kernel hypervisor that people trust for VMs, including moving Windows guests from VMware. Critics say its attack surface is large and it has had guest-to-host escape bugs.
Free Linux kernel hypervisor that people trust for VMs, including moving Windows guests from VMware. Critics say its attack surface is large and it has had guest-to-host escape bugs.
41 people gave an opinion
- recommend it
- 32
- criticize it
- 9
- approval share
- 78%
Recommended in 12 of 13 months
- November 2025: recommended
- December 2025: recommended
- January 2026: recommended
- February 2026: recommended
- March 2026: not recommended
- April 2026: recommended
- May 2026: recommended
- June 2026: recommended
- July 2026: recommended
- August 2026: recommended
- September 2026: recommended
- October 2026: recommended
- November 2026: recommended (month in progress)
Why it carries the badge
- 32 people recommend itNeeds 10 or more, met.
- 3.6 recommenders for every criticNeeds 2 to 1 or better, met.
- Recommended in 12 of 13 monthsNeeds 4 or more, met.
The same three rules apply to every product, and the badge can’t be bought. How the badge works
What people say about it
The reasons people give, with the number of comments that give each one. Open a reason to read what they said.
Why people recommend it
Each mark is one comment
Free, open hypervisor
“good on KVM and others for pushing open hypervisor technology”
Comment from 8 Sep 2026 in “Leaving VMware just got harder after Broadcom pulled VDDK downloads” “great and free KVM virtualization”
Comment from 24 Jul 2026 in “Making Xen's dom0 I/O path NUMA aware” Smooth move from VMware
“I've done it a few times, moving between VMware and KVM of Windows guests pretty much just worked”
Comment from 19 Jun 2026 in “Tesco moving 40k server workloads off VMware amid Broadcom's abusive conduct” “those that found their store-brand version of KVM to replace VMware are certainly happy”
Comment from 10 Apr 2026 in “"Negative" views of Broadcom driving VMware migrations, rival says” “at a more convenient level using KVM than full-fledged VMware VMs”
Comment from 12 Jun 2026 in “Are we defaulting to VM-level sandboxing before understanding the threat model?” Strong security record
“CVEs for runc are much more frequent than CVEs for KVM.”
Comment from 29 Sep 2026 in “Show HN: NSL – WSL for Linux” “Kernel KVM has a very good record for security”
Comment from 7 Jul 2026 in “Januscape: Guest-to-Host Escape in KVM/x86 [CVE-2026-53359]” “KVM escapes are very rare”
Comment from 12 Jul 2026 in “Theo de Raadt: "You've been smoking something mind altering" (2007)” Works reliably out of the box
“via KVM and it seems to work well”
Comment from 26 Jan 2026 in “Apple, What Have You Done?” “you are right, it just works”
Comment from 13 Feb 2026 in “AWS Adds support for nested virtualization” “kvm itself feels good too”
Comment from 23 Dec 2025 in “Fabrice Bellard Releases MicroQuickJS”
What people warn about
Each mark is one comment
Large, complex attack surface
“shadow MMU is highly complicated legacy code (i.e. outside of the main happy path)”
Comment from 7 Aug 2026 in “Zapscape (CVE-2026-64561)” “the surface area of kvm and qemu is still very large and difficult to reason about”
Comment from 27 Aug 2026 in “VMs won't contain cyber-capable agents” “KVM has a much larger attack surface than Xen”
Comment from 24 Jul 2026 in “Making Xen's dom0 I/O path NUMA aware” Guest-to-host escape bugs
“kvm can be leveraged to gain access to the host by means of exploits”
Comment from 29 Aug 2026 in “Show HN: MicroVM daemon, deploy any Docker image” “it was KVM that turned out to have the worst bugs, not QEMU”
Comment from 26 Aug 2026 in “VMs won't contain cyber-capable agents” “2 KVM guest->host control ones”
Comment from 10 Oct 2026 in “Telegram Desktop vulnerability allowed any user's file to be stolen” Not perfect, has had bugs
“kvm is also pretty good, but not perfect”
Comment from 18 May 2026 in “The foundations of a provably secure operating system (PSOS) (1979) [pdf]” “A kvm hypervisor is not perfect”
Comment from 18 Jan 2026 in “Singularity Rootkit: SELinux bypass and netlink filter (ss/conntrack hidden)”
Other hypervisors people recommend
The four most recommended other hypervisors, with the same counts for each, so you can compare like for like. The tick on each bar marks the 2 to 1 line the badge needs.
| Product | Recommend | Criticize | Approval | Months | Owned | Badge |
|---|---|---|---|---|---|---|
| Proxmox VE | 208 | 60 | 78% | 12 | 3 yrs16 owners | Approved |
| Incus | 90 | 8 | 92% | 12 | 6 mo5 owners | Approved |
| KVMThis page | 32 | 9 | 78% | 12 | — | Approved |
| Hyper-V | 17 | 9 | 65% | 9 | — | — |
| bhyve hypervisor | 17 | 4 | 81% | 8 | — | Approved |
What people said
38 of the 42 comments that mention it, newest first. Each links to the original comment.
“illustrates the value of running all web services under KVM rather than bare metal”
“2 KVM guest->host control ones”
“KVM relies on the Linux kernel to provide isolation”
“CVEs for runc are much more frequent than CVEs for KVM.”
“superior hypervisors like KVM and bhyve”
“But is trivial with Proxmox/KVM.”
“I would trust KVM over Hyper-V any day”
“good on KVM and others for pushing open hypervisor technology”
“Move the work loads to KVM, and invest in your own employees”
“kvm can be leveraged to gain access to the host by means of exploits”
“dedicated KVM virtual machine that lives on a system under my desk”
“the surface area of kvm and qemu is still very large and difficult to reason about”
“it was KVM that turned out to have the worst bugs, not QEMU”
“addition of KVM! I remember when this was not a given”
“Maybe through KVM, but that already requires privilege in the VM, right?”
“provides hardware level isolation (the CPU hypervisor etc), that's the point”
“shadow MMU is highly complicated legacy code (i.e. outside of the main happy path)”
“you don't touch hardware virtualization with a 10 foot pole”
“KVM won by having that realization earlier than most.”
“KVM is/became a kernel module, and its development is now 'in-tree' for mainline kernel”
“KVM has a much larger attack surface than Xen”
“great and free KVM virtualization”
“KVM escapes are very rare”
“Kernel KVM has a very good record for security”
“I've done it a few times, moving between VMware and KVM of Windows guests pretty much just worked”
“at a more convenient level using KVM than full-fledged VMware VMs”
“kvm is also pretty good, but not perfect”
“excellent virtual machine platforms (KVM, Xen and even VMWare)”
“Emulators can take you quite far, though you need to research some of them on the net”
“those that found their store-brand version of KVM to replace VMware are certainly happy”
“ended up on a full KVM VM”
“you are right, it just works”
“I have a great experience especially with GPU passthrough.”
“via KVM and it seems to work well”
“A kvm hypervisor is not perfect”
“kvm itself feels good too”
“One interesting cheat code is to start by only running inside KVM.”
“KVM is awesome enough that there isn't a lot of room left to differentiate at the hypervisor level.”
Counts come from 1,795,640 Hacker News comments, November 2025 to November 2026. How we count. Report a mistake.