CVE-2026-46316
EPSS 0.1%Marketing campaign ("ITScape") amplifies routine kernel patch; PoC claims unverified, no KEV, EPSS negligible.
What: Reference counting bug in Linux kernel KVM/arm64 vGIC-ITS translation cache invalidation allowing concurrent double-free; no CVSS assigned, EPSS 0.0005%.
Why it matters: Social media claims "guest-to-host escape" and "PoC" under marketing name "ITScape," but NVD description documents a race condition in cache cleanup, not a direct escape vector. No KEV listing, no official PoC confirmed, EPSS near-zero. Vendor (Linux) patched the bug as a correctness fix, not emergency response.
Where it's seen: Coordinated Bluesky posts from low-engagement accounts rebranding a routine kernel fix as critical escape exploit; sensationalized framing mismatches actual advisory scope.
RISK: LOW — Reference counting race is fixable; no confirmed guest-to-host exploitation path demonstrated.
Description
In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: vgic-its: Drop the translation cache reference only for the erased entry vgic_its_invalidate_cache() walks the per-ITS translation cache with xa_for_each() and drops the cache's reference on each entry with vgic_put_irq(). It puts the iterated pointer, though, rather than the value returned by xa_erase(). The function is called from contexts that do not exclude one another: the ITS command handlers hold its_lock, the GITS_CTLR write path holds cmd_lock, and the path that clears EnableLPIs in a redistributor's GICR_CTLR holds neither. Two or more of them can drain the same cache concurrently, and if each one observes the same entry, erases it and then puts it, the single reference the cache holds on that entry is dropped more than once. The entry can then be freed while an ITE still maps it. xa_erase() is atomic and returns the previous entry, so put only the entry that this context actually removed. The cache reference is then dropped exactly once per entry even when the invalidations run concurrently, and the behavior is unchanged when only one context runs.