{"id":"CVE-2026-80723","state":"PUBLISHED","title":"of: reserved_mem: prevent OOB when too many dynamic regions are defined","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nof: reserved_mem: prevent OOB when too many dynamic regions are defined\n\nOn boot, fdt_scan_reserved_mem() saves each dynamically-placed\n/reserved-memory subnode into a local array of size\nMAX_RESERVED_REGIONS.\n\nIf the device tree defines more than MAX_RESERVED_REGIONS\ndynamically-placed regions, fdt_scan_reserved_mem() writes past the\nend of the local array.\n\nAdd a bounds check that logs an error and skips the excess regions,\nrestoring the original behavior.","publishedAt":"2026-08-28T06:53:18.485Z","updatedAt":"2026-10-16T19:26:35.582Z","severity":{"score":8.4,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"9a0fe62f93ede02c27aaca81112af1e59c8c0979","status":"affected","lessThan":"68d27250c9e81ab7764603e346c2b1017cb53adf","versionType":"git"},{"version":"8a6e02d0c00e7b62e6acb74146878bb91e9e7e31","status":"affected","lessThan":"cfa7e2734877330d6c10e0f33953905486c4530c","versionType":"git"},{"version":"8a6e02d0c00e7b62e6acb74146878bb91e9e7e31","status":"affected","lessThan":"de8ccbd6bf4efe7a059e2c483789936009e10f42","versionType":"git"},{"version":"8a6e02d0c00e7b62e6acb74146878bb91e9e7e31","status":"affected","lessThan":"db3dbdfea1b8f38774419c5c2c14e4b81c48708d","versionType":"git"},{"version":"6.12.13","status":"affected","lessThan":"6.12.103","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/of/of_reserved_mem.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.13","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.13","versionType":"semver"},{"version":"6.12.103","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.44","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.8","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/of/of_reserved_mem.c"]}],"references":["https://git.kernel.org/stable/c/68d27250c9e81ab7764603e346c2b1017cb53adf","https://git.kernel.org/stable/c/cfa7e2734877330d6c10e0f33953905486c4530c","https://git.kernel.org/stable/c/de8ccbd6bf4efe7a059e2c483789936009e10f42","https://git.kernel.org/stable/c/db3dbdfea1b8f38774419c5c2c14e4b81c48708d"],"weaknesses":[],"ingestedAt":"2026-10-29T20:13:07.220Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/80xxx/CVE-2026-80723.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-80723","state":"PUBLISHED","datePublished":"2026-08-28T06:53:18.485Z","dateUpdated":"2026-10-16T19:26:35.582Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-08-26T14:34:25.788Z"},"containers":{"cna":{"title":"of: reserved_mem: prevent OOB when too many dynamic regions are defined","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nof: reserved_mem: prevent OOB when too many dynamic regions are defined\n\nOn boot, fdt_scan_reserved_mem() saves each dynamically-placed\n/reserved-memory subnode into a local array of size\nMAX_RESERVED_REGIONS.\n\nIf the device tree defines more than MAX_RESERVED_REGIONS\ndynamically-placed regions, fdt_scan_reserved_mem() writes past the\nend of the local array.\n\nAdd a bounds check that logs an error and skips the excess regions,\nrestoring the original behavior."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"9a0fe62f93ede02c27aaca81112af1e59c8c0979","status":"affected","lessThan":"68d27250c9e81ab7764603e346c2b1017cb53adf","versionType":"git"},{"version":"8a6e02d0c00e7b62e6acb74146878bb91e9e7e31","status":"affected","lessThan":"cfa7e2734877330d6c10e0f33953905486c4530c","versionType":"git"},{"version":"8a6e02d0c00e7b62e6acb74146878bb91e9e7e31","status":"affected","lessThan":"de8ccbd6bf4efe7a059e2c483789936009e10f42","versionType":"git"},{"version":"8a6e02d0c00e7b62e6acb74146878bb91e9e7e31","status":"affected","lessThan":"db3dbdfea1b8f38774419c5c2c14e4b81c48708d","versionType":"git"},{"version":"6.12.13","status":"affected","lessThan":"6.12.103","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/of/of_reserved_mem.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.13","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.13","versionType":"semver"},{"version":"6.12.103","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.44","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.8","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/of/of_reserved_mem.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/68d27250c9e81ab7764603e346c2b1017cb53adf"},{"url":"https://git.kernel.org/stable/c/cfa7e2734877330d6c10e0f33953905486c4530c"},{"url":"https://git.kernel.org/stable/c/de8ccbd6bf4efe7a059e2c483789936009e10f42"},{"url":"https://git.kernel.org/stable/c/db3dbdfea1b8f38774419c5c2c14e4b81c48708d"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","baseScore":8.4,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - The overflow only runs in __init boot-time fdt_scan_reserved_mem() while parsing /reserved-memory from the bootloader-provided DTB; there is no post-boot syscall, ioctl, netlink, or network-stack path to this code on OF/DT platforms (arm/arm64/RISC-V/ppc/mips/etc.).\nAC:L - An attacker who can supply a device tree simply defines more than MAX_RESERVED_REGIONS (64) dynamically-placed /reserved-memory subnodes (size without reg); each extra node deterministically performs another unchecked write past dynamic_nodes[] without races or layout luck.\nPR:N - Triggering requires only a crafted device tree delivered at boot (e.g., compromised firmware/OTA image, supply-chain DTB, unauthenticated PXE/TFTP netboot), not privileges on the victim OS; unprivileged local users and user-namespace capabilities cannot reach this __init-only path.\nUI:N - Once a malicious DTB is installed, the stack overflow occurs automatically during early_init_fdt_scan_reserved_mem() before userspace starts; no cooperative action by another user or administrator is required beyond normal boot.\nS:U - Impact is confined to early-boot kernel stack/memory corruption within the same host kernel; this is not a VM escape, guest-to-host breakout, IOMMU boundary bypass, or other cross-security-authority scenario.\nC:H - Each OOB store writes an attacker-influenced FDT node offset past dynamic_nodes[MAX_RESERVED_REGIONS] onto the kernel stack, corrupting adjacent locals and potentially frame/link registers; per kernel guidance, stack OOB writes enable high confidentiality impact.\nI:H - This is a stack buffer overflow (CWE-121/787) during __init: repeated int writes past the 64-element dynamic_nodes[] array can corrupt return addresses and control flow in early boot before full hardening, enabling arbitrary kernel code execution.\nA:H - Unchecked OOB writes into the boot-time stack typically cause immediate kernel panic/oops during fdt_scan_reserved_mem() (corrupted count/fdt pointers or trashed frame), denying availability on every boot with a crafted or over-limit DT."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-29T06:22:40.126Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.12.13","versionEndExcluding":"6.12.103"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.13","versionEndExcluding":"6.18.44"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.13","versionEndExcluding":"7.1.8"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.13","versionEndExcluding":"7.2"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2026-80723","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"version":"2.0.3","timestamp":"2026-10-16T19:21:00.622788Z"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-16T19:26:35.582Z"}}]}}}