{ "schemaVersion": 1, "attribution": [ { "source": "CISA Known Exploited Vulnerabilities", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog", "licence": "US government work" }, { "source": "GitHub Advisory Database", "url": "https://github.com/advisories", "licence": "CC BY 4.0" }, { "source": "Have I Been Pwned", "url": "https://haveibeenpwned.com/", "licence": "CC BY 4.0" }, { "source": "CVE Program (CVE records)", "url": "https://www.cve.org/Legal/TermsOfUse", "licence": "CVE Terms of Use", "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.", "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy." }, { "source": "FIRST EPSS", "url": "https://www.first.org/epss/", "licence": "free to use; FIRST requests attribution" } ], "record": { "id": "CVE-2026-74568", "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-74568", "idYear": 2026, "status": "PUBLISHED", "publishedAt": "2026-08-15T12:28:08.859Z", "updatedAt": "2026-10-16T19:05:56.525Z", "importedAt": "2026-10-24T01:58:30.346Z", "snapshot": { "id": "cve_2026-10-24_midnight_baseline", "at": "2026-10-24T00:00:00.000Z", "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z" }, "facts": { "title": "KVM: arm64: vgic: Fix race between LPI release and re-registration", "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: arm64: vgic: Fix race between LPI release and re-registration\n\nFix a potential race between decrementing an LPI's reference count and\nevicting that structure from the LPI xarray.\n\nLPI structures are maintained in the VGIC LPI xarray (dist->lpi_xa).\nWhen the reference count of an LPI structure drops to zero,\nvgic_release_lpi_locked() removes the structure from the xarray and\nfrees it under the xarray lock.\n\nHowever, the release of an LPI can race with a concurrent LPI\nre-registration with the same INTID via vgic_add_lpi() on another CPU,\nsince the reference count drop and the xarray eviction are not performed\nin a single atomic step. This can happen e.g. if the guest issues a\nDISCARD while the LPI is still referenced from a vCPU's active-pending\nlist (ap_list), and the same INTID is re-mapped via MAPTI.\n\nParticularly, vgic_release_lpi_locked() is called from two distinct\npaths: direct release via vgic_put_irq(), and deferred release via\nvgic_release_deleted_lpis(). During direct release, the issue can result\nin deleting a newly registered LPI from the xarray:\n\n CPU0 (Releasing LPI) CPU1 (Adding new LPI)\n ==================== =====================\n vgic_put_irq()\n __vgic_put_irq()\n refcount_dec_and_test()\n vgic_add_lpi()\n xa_lock_irqsave()\n old_irq = xa_load(.., intid)\n vgic_try_get_irq_ref(old_irq) == false\n new IRQ inserted --> __xa_store(.., intid, ..)\n xa_unlock_irqrestore()\n xa_lock_irqsave();\n vgic_release_lpi_locked()\n __xa_erase(.., irq->intid) <-- BUG: new IRQ is erased\n kfree_rcu(old_irq)\n\nDuring the deferred release path, the old IRQ can be leaked:\n\n CPU0 (Releasing LPI) CPU1 (Adding new LPI)\n ==================== =====================\n vgic_put_irq_norelease()\n __vgic_put_irq()\n refcount_dec_and_test()\n irq->pending_release = true\n vgic_add_lpi()\n xa_lock_irqsave()\n old_irq = xa_load(.., intid)\n vgic_try_get_irq_ref(oldirq) == false\n BUG: old IRQ overwritten --> __xa_store(.., intid, ..)\n xa_unlock_irqrestore()\n\n vgic_release_deleted_lpis()\n xa_lock_irqsave()\n xa_for_each() { .. } <-- old IRQ with pending_release = true\n is gone, so it cannot be released\n\nTo fix the direct release path, move the reference count drop inside\nthe xarray lock, making sure that vgic_add_lpi() never encounters the\nto-be-released LPI.\n\nIn the deferred release path, the refcount drop must happen under a raw\nspinlock, so the xarray lock cannot be grabbed, and the same solution\ndoes not work. Instead, update vgic_add_lpi(), so that if it evicts\nan LPI from the xarray, it takes on the responsibility of freeing it.\nConsequently, an LPI may now be freed concurrently after a deferred\nrelease drops the refcount, so accessing the pending_release field is no\nlonger safe from use-after-free. Delete all uses of the flag, and update\nvgic_release_deleted_lpis() to identify orphaned LPIs purely based on\ntheir refcount.", "affected": [ { "vendor": "Linux", "product": "Linux", "defaultStatus": "unaffected", "versions": [ { "version": "3a08a6ca7c373198c84e2a8c025c395ee966ff8a", "status": "affected", "versionType": "git", "lessThan": "f8e5715a37378ea1a140ee1162fa441e149c5142" }, { "version": "3a08a6ca7c373198c84e2a8c025c395ee966ff8a", "status": "affected", "versionType": "git", "lessThan": "292e80a159aa88635bf668a7212cfdf526b8bd52" }, { "version": "3a08a6ca7c373198c84e2a8c025c395ee966ff8a", "status": "affected", "versionType": "git", "lessThan": "cbfe2b24a1ea9de35032dbdd100fdc700f5be92d" } ] }, { "vendor": "Linux", "product": "Linux", "defaultStatus": "affected", "versions": [ { "version": "6.17", "status": "affected" }, { "version": "0", "status": "unaffected", "versionType": "semver", "lessThan": "6.17" }, { "version": "6.18.57", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.18.*" }, { "version": "7.1.8", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "7.1.*" }, { "version": "7.2", "status": "unaffected", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*" } ] } ] } } }