{"metadata": {"vulnerability": "CVE-2026-79979", "count": 9, "kinds": {"milestone": 4, "sighting": 1, "kev": 0, "other": 4}}, "data": [{"timestamp": "2026-08-25T16:06:32.777Z", "date_only": false, "value": "2026-08-25T16:06:32.777Z", "kind": "milestone", "label": "Reserved", "source": "cvelistv5", "record": "CVE-2026-79979", "field": "cveMetadata.dateReserved"}, {"timestamp": "2026-10-23T19:56:16.111Z", "date_only": false, "value": "2026-10-23T19:56:16.111Z", "kind": "milestone", "label": "Published", "source": "cvelistv5", "record": "CVE-2026-79979", "field": "cveMetadata.datePublished"}, {"timestamp": "2026-10-23T19:56:16.111Z", "date_only": false, "value": "2026-10-23T19:56:16.111Z", "kind": "other", "label": "Updated", "source": "cvelistv5", "record": "CVE-2026-79979", "field": "cveMetadata.dateUpdated"}, {"timestamp": "2026-10-23T19:56:16.111Z", "date_only": false, "value": "2026-10-23T19:56:16.111Z", "kind": "other", "label": "Updated", "source": "cvelistv5 / zephyr", "record": "CVE-2026-79979", "field": "containers.cna.providerMetadata.dateUpdated"}, {"timestamp": "2026-10-23T20:05:58.507Z", "date_only": false, "value": "2026-10-23T20:05:58.507357Z", "kind": "sighting", "label": "Seen", "source": "https://infosec.exchange/users/cve/statuses/117492020498695922", "record": "CVE-2026-79979", "field": "creation_timestamp", "uuid": "671b05c2-203e-4693-aebd-b64b32aa7d25", "content": "CVE-2026-79979 Stale TLB entries after demand-paging page-out let arm64 user threads access reused physical frames The arm64 MMU backend invalidates a single virtual address from the TLB with invalidate_tlb_page() in arch/arm64/core/mmu.c, which issued TLBI VAE1{IS} with an operand of virt >> 12. That operand encodes the ASID in bits [63:48], so the invalidation only ever matched ASID 0 (the kernel page tables) and global entries. Memory domains, however, are allocated ASIDs starting at 1 in arch_mem_domain_init(), and every domain-private leaf created by private_map() is mapped with MT_NG, i.e. non-global. A domain's cached translation therefore survived the invalidation.\nAll callers of invalidate_tlb_page() are demand-paging paths. When the eviction algorithm reclaims a frame, page_frame_prepare_locked() in kernel/mmu.c calls arch_mem_page_out(), which marks the kernel leaf invalid, propagates the invalid descriptor into every domain via sync_domains(), and then flushes only ASID 0. do_page_fault() immediately reuses the very same page frame for the incoming mapping through arch_mem_page_in(). A user thread that had already touched the evicted page \u2014 a k_mem_partition added with arch_mem_domain_partition_add(), or its own stack mapped by map_thread_stack() \u2014 retains a valid EL0 read/write translation to that physical frame under its own ASID.\nUnprivileged code running in a user thread can drive memory pressure to force eviction and then keep accessing the stale address, obtaining read and write access to whatever the kernel subsequently placed in that frame: supervisor data, another memory domain's partition, or another thread's stack. This defeats the isolation that CONFIG_USERSPACE is meant to enforce, allowing information disclosure and memory corruption up to full compromise of the system.\nThe fix switches the implementation to TLBI VAAE1{IS}, which matches every ASID and both global and non-global entries, so no domain-tagged translation survives a page out, dirty-bit update or access-flag clear. Exploitation requires an arm64 build with both CONFIG_USERSPACE and CONFIG_DEMAND_PAGING enabled, an active backing store, and at least one demand-paged page that is also privately mapped into a user memory domain. The same commit additionally stops globalize_table() from stripping EL0 permission and non-global attributes off domain-private leaves during paging synchronization, which previously caused user threads to lose access to their own partitions and stacks.\nhttps://www.cve.org/CVERecord?id=CVE-2026-79979https://github.com/zephyrproject-rtos/zephyr/commit/d732e9f808f16911d06769b3f756246f3528669fhttps://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-6pqm-hfxf-48qv#zephyrproject #zephyr#CVE_2026_79979#bot", "url": "https://infosec.exchange/users/cve/statuses/117492020498695922"}, {"timestamp": "2026-10-23T20:17:27.783Z", "date_only": false, "value": "2026-10-23T20:17:27.783", "kind": "milestone", "label": "Published", "source": "fkie_nvd \u00b7 FKIE_CVE-2026-79979", "record": "FKIE_CVE-2026-79979", "field": "published"}, {"timestamp": "2026-10-26T00:00:00Z", "date_only": false, "value": "2026-10-26T00:00:00Z", "kind": "milestone", "label": "Published", "source": "osv_ubuntu \u00b7 UBUNTU-CVE-2026-79979", "record": "UBUNTU-CVE-2026-79979", "field": "published"}, {"timestamp": "2026-10-26T00:00:00Z", "date_only": false, "value": "2026-10-26T00:00:00Z", "kind": "other", "label": "Updated", "source": "osv_ubuntu \u00b7 UBUNTU-CVE-2026-79979", "record": "UBUNTU-CVE-2026-79979", "field": "modified"}, {"timestamp": "2026-10-26T13:52:21.763Z", "date_only": false, "value": "2026-10-26T13:52:21.763", "kind": "other", "label": "Updated", "source": "fkie_nvd \u00b7 FKIE_CVE-2026-79979", "record": "FKIE_CVE-2026-79979", "field": "lastModified"}]}