Is CVE-2026-99287 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-99287 being exploited in the wild.

How severe is CVE-2026-99287?

Informational severity, published 10 November 2026.

Which products and versions are affected?

Linux Kernel multiple versions through 7.3.y.

Is there a fix for CVE-2026-99287?

A patch was published on 2026-11-10: committed upstream as f96f16592a32430a0582309d73a873b6d3ee2bdb Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-99287 attacked?

It is attacked with local access, in an operating system.

Am I affected by CVE-2026-99287?

Check whether you run Linux Kernel at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-99287: Linux kernel xen-netback double unmap memory corruption

CVE-2026-99287 · Severity: info · Published 2026-11-10

The Linux kernel's Xen virtual network backend driver (xen-netback) contains a flaw in how it cleans up ring pointers when network ring mapping fails. If a second cleanup attempt occurs, the driver tries to unmap already-freed memory, which could lead to memory corruption or system instability on virtual machines using Xen networking.

Technologies: Linux Kernel. Vendors: Linux.

Quick answers

Is CVE-2026-99287 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-99287 being exploited in the wild.
How severe is CVE-2026-99287?: Informational severity, published 10 November 2026.
Which products and versions are affected?: Linux Kernel multiple versions through 7.3.y.
Is there a fix for CVE-2026-99287?: A patch was published on 2026-11-10: committed upstream as f96f16592a32430a0582309d73a873b6d3ee2bdb Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-99287 attacked?: It is attacked with local access, in an operating system.
Am I affected by CVE-2026-99287?: Check whether you run Linux Kernel at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A double-free condition exists in xenvif_unmap_frontend_data_rings() where ring pointers are not zeroed after unmapping. If xenvif_map_frontend_data_rings() fails during a retry when rings are already mapped, the cleanup path calls unmap a second time on stale pointers. The fix zeros the ring pointers (tx.sring and rx.sring) after calling xenbus_unmap_ring_vfree(), preventing the double-unmap. This affects the kernel's Xen networking backend driver in the net/xen-netback subsystem.

Affected products

Linux kernel multiple versions through 7.3.y

Timeline

2026-11-10: disclosed
2026-11-10: patched: committed upstream as f96f16592a32430a0582309d73a873b6d3ee2bdb

References

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