Greg Kroah-Hartman's Linux stable tree released seven kernels in a matter of minutes, spanning every active branch from the fresh 7.3.3 down to the nearly decade-old 5.10.274. All seven carried the identical trio of security patches, addressing use-after-free and race conditions in the Xen hypervisor's network and block backend drivers. The fixes, authored by SUSE's Juergen Gross and Jan Beulich, pose a guest-to-host privilege-escalation risk on Xen hosts but don't affect typical desktop or laptop users. Because 5.10 and 5.15 reach end-of-life in December 2026, this batch is among the final standard updates for those branches, and all seven are now available on the kernel.org mirrors with PGP signatures.
Linux ships seven kernel updates at once, all patching the same Xen hole
Today, the stable tree released seven version numbers back-to-back, every active branch carrying the same three virtualization security fixes.
Friday's Linux kernel stable release was one of those days where the plumbing just worked. Greg Kroah-Hartman pushed seven version numbers out within a handful of minutes, spanning every active maintenance branch from the freshest 7.3.3 down to the nearly decade-old 5.10.274.
The unusual part is what all seven shared. Rather than each branch picking up its own random mix of fixes, every one carried the exact same three security patches. Three Xen virtualization fixes, delivered across the entire supported stack in a single coordinated drop.
Not complicated to explain, but worth pausing over. The releases landed in order, sequenced roughly four minutes apart and mirrored through the late afternoon UTC. 5.10.274 went out first at 18:19. 7.3.3 wrapped things up at 18:44. In between came 5.15.225, 6.1.192, 6.6.162, 6.12.116, and 6.18.62, each spaced just enough to be individually traceable.
That kind of full-spectrum rollout is the stable model working exactly as designed. It's just satisfying to actually watch it happen.
What the three fixes actually are
These are small, surgical changes, and that's precisely why they survived the backport trip across six major version series intact. They cover use-after-free and race conditions in the network and block backend drivers for Xen, the open-source hypervisor. Both drivers live on the host side of a virtualization setup, talking to paravirtualized guests, which is what actually determines who should bother.
Here's the breakdown.
XSA-526, or CVE-2026-100080, is a use-after-free in the network backend when reading statistics. The driver keeps per-queue stats under RCU, a lock-free synchronization scheme. When queues were torn down after an error, the old code freed that memory without waiting for readers already inside it. A sysfs call hitting that window could touch memory that was already freed or already handed out again. The fix calls synchronize_net() before the queue gets freed.
Next is XSA-527 (CVE-2026-100081), still in the network backend, this time about deferring a multicast address-list free. The function xenvif_mcast_addr_list_free() has to run only after all TX and RX processing has completely stopped, so it can't fire from the wrong point in the disconnect path. The fix shifts the call past the synchronization barrier inside backend_disconnect().
The third fix, XSA-528 (CVE-2026-100082), lands in the block backend. Reading block-device I/O stats through sysfs while a frontend device is being torn down could trigger a use-after-free or a NULL pointer dereference, because the readout wasn't synchronized with the underlying data getting freed. That one is protected by wrapping the read-and-free sequence in an rwlock.
The upshot is that a malicious or simply mischievous guest could potentially crash the host, escalate privileges, or reach the physical machine running all the guests. That's a guest-to-host problem on Xen hosts, not a threat to your average desktop or laptop. If you're not running Xen virtualization, none of this touches you.
The patches come from SUSE's Xen security team, Juergen Gross and Jan Beulich, tracked under Xen Security Advisories, the framework the virtualization world uses to coordinate findings. Two of the three were reported by Yehyeong Lee of Korea's ISSLab, alongside a community reporter going by "kerhunt." You're in good hands when two of the most cited Xen researchers in the field are holding the pen.
The same fix, across a decade of kernels
This uniformity isn't a fluke or a release-process accident. When a security issue matters enough, Greg's stable tree backports it to every currently supported branch in one go. It's the whole point of the stable model, letting cloud providers, distros, and embedded vendors running anything from a 2020 LTS kernel to this year's mainline close the same hole in a single update.
What you got Friday was that model in full view. Seven version numbers that differ only in their trailing digit, yet share one common payload.
I'll let you in on a detail that's easy to miss. Each release's changelog contains exactly four commits: the version-tag commit plus those three upstream fixes. Nothing extra bundled in by accident. Somewhere out there is a sysadmin who greps changelogs for sport on release day, and this is the kind of day that makes their week.
Today's patches are narrowly about Xen, but each version number sits inside a series with its own reputation. 6.6 is where the EEVDF scheduler landed. 6.1 brought Rust kernel modules. 6.12 merged real-time scheduling into mainline and now rides in Debian 13 and RHEL 10. The newest line, 7.3, pushed btrfs throughput up roughly 95% on certain tasks and slashed Kernel Samepage Merging latency from about 700 ms to under 2 ms under heavy memory use. The 95% bump is measured on specific tasks, so take it as a best case. However, at the same time, a KSM latency cut like that is exactly the kind of pain that shows up in real production.
One thing worth flagging is a date. Both 5.10 and 5.15 reach their mainline LTS end of life in December 2026. That makes Friday's batch effectively among the final standard security updates for those branches, with the CIP SLTS program carrying 5.10 further into the early 2030s for embedded and IoT deployments that can't migrate on short notice. If you're still on either of those, get ahead of it now.
Linux kernel 7.3.3 released
Linux kernel version 7.3.3 is now available:
Full source: https://cdn.kernel.org/pub/linux/kernel/v7.x/linux-7.3.3.tar.xz
Patch: https://cdn.kernel.org/pub/linux/kernel/v7.x/patch-7.3.3.xz
PGP Signature: https://cdn.kernel.org/pub/linux/kernel/v7.x/linux-7.3.3.tar.sign
You can view the summary of the changes at the following URL:
https://git.kernel.org/stable/ds/v7.3.3/v7.3.2
Linux kernel 6.18.62 released
Linux kernel version 6.18.62 is now available:
Full source: https://cdn.kernel.org/pub/linux/kernel/v6.x/linux-6.18.62.tar.xz
Patch: https://cdn.kernel.org/pub/linux/kernel/v6.x/patch-6.18.62.xz
PGP Signature: https://cdn.kernel.org/pub/linux/kernel/v6.x/linux-6.18.62.tar.sign
You can view the summary of the changes at the following URL:
https://git.kernel.org/stable/ds/v6.18.62/v6.18.61
Linux kernel 6.12.116 released
Linux kernel version 6.12.116 is now available:
Full source: https://cdn.kernel.org/pub/linux/kernel/v6.x/linux-6.12.116.tar.xz
Patch: https://cdn.kernel.org/pub/linux/kernel/v6.x/patch-6.12.116.xz
PGP Signature: https://cdn.kernel.org/pub/linux/kernel/v6.x/linux-6.12.116.tar.sign
You can view the summary of the changes at the following URL:
https://git.kernel.org/stable/ds/v6.12.116/v6.12.115
Linux kernel 6.6.162 released
Linux kernel version 6.6.162 is now available:
Full source: https://cdn.kernel.org/pub/linux/kernel/v6.x/linux-6.6.162.tar.xz
Patch: https://cdn.kernel.org/pub/linux/kernel/v6.x/patch-6.6.162.xz
PGP Signature: https://cdn.kernel.org/pub/linux/kernel/v6.x/linux-6.6.162.tar.sign
You can view the summary of the changes at the following URL:
https://git.kernel.org/stable/ds/v6.6.162/v6.6.161
Linux kernel 6.1.192 released
Linux kernel version 6.1.192 is now available:
Full source: https://cdn.kernel.org/pub/linux/kernel/v6.x/linux-6.1.192.tar.xz
Patch: https://cdn.kernel.org/pub/linux/kernel/v6.x/patch-6.1.192.xz
PGP Signature: https://cdn.kernel.org/pub/linux/kernel/v6.x/linux-6.1.192.tar.sign
You can view the summary of the changes at the following URL:
https://git.kernel.org/stable/ds/v6.1.192/v6.1.191
Linux kernel 5.15.225 released
Linux kernel version 5.15.225 is now available:
Full source: https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.15.225.tar.xz
Patch: https://cdn.kernel.org/pub/linux/kernel/v5.x/patch-5.15.225.xz
PGP Signature: https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.15.225.tar.sign
You can view the summary of the changes at the following URL:
https://git.kernel.org/stable/ds/v5.15.225/v5.15.224
Linux kernel 5.10.274 released
Linux kernel version 5.10.274 is now available:
Full source: https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.10.274.tar.xz
Patch: https://cdn.kernel.org/pub/linux/kernel/v5.x/patch-5.10.274.xz
PGP Signature: https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.10.274.tar.sign
You can view the summary of the changes at the following URL:
https://git.kernel.org/stable/ds/v5.10.274/v5.10.273
