{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2023-53481", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-10-01T11:39:39.402Z", "datePublished": "2025-10-01T11:42:49.825Z", "dateUpdated": "2026-08-05T09:14:17.891Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T09:14:17.891Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nubi: ubi_wl_put_peb: Fix infinite loop when wear-leveling work failed\n\nFollowing process will trigger an infinite loop in ubi_wl_put_peb():\n\n\tubifs_bgt\t\tubi_bgt\nubifs_leb_unmap\n ubi_leb_unmap\n ubi_eba_unmap_leb\n ubi_wl_put_peb\twear_leveling_worker\n e1 = rb_entry(rb_first(&ubi->used)\n\t\t\t e2 = get_peb_for_wl(ubi)\n\t\t\t ubi_io_read_vid_hdr // return err (flash fault)\n\t\t\t out_error:\n\t\t\t ubi->move_from = ubi->move_to = NULL\n\t\t\t wl_entry_destroy(ubi, e1)\n\t\t\t ubi->lookuptbl[e->pnum] = NULL\n retry:\n e = ubi->lookuptbl[pnum];\t// return NULL\n\tif (e == ubi->move_from) {\t// NULL == NULL gets true\n\t goto retry;\t\t\t// infinite loop !!!\n\n$ top\n PID USER PR NI VIRT RES SHR S %CPU %MEM COMMAND\n 7676 root 20 0 0 0 0 R 100.0 0.0 ubifs_bgt0_0\n\nFix it by:\n 1) Letting ubi_wl_put_peb() returns directly if wearl leveling entry has\n been removed from 'ubi->lookuptbl'.\n 2) Using 'ubi->wl_lock' protecting wl entry deletion to preventing an\n use-after-free problem for wl entry in ubi_wl_put_peb().\n\nFetch a reproducer in [Link]." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The vulnerable path is reached only from local activity — file writes/unlinks on a mounted UBIFS filesystem driving `ubifs_leb_unmap()`, or `UBI_IOCEBER`/`UBI_IOCEBUNMAP` ioctls on `/dev/ubiX_Y`. There is no network-facing consumer of the UBI wear-leveling layer.\nAC:L - The attacker supplies both the concurrency (unbounded parallel LEB unmaps via ordinary filesystem writes/deletes or a tight ioctl loop) and sustained write pressure that keeps the wear-leveling worker running continuously on flash whose read/ECC errors are the expected operating condition UBI is built to handle; once the error path fires, the `NULL == ubi->move_from` comparison is deterministic, not probabilistic.\nPR:L - Any unprivileged local user with write access to a UBIFS mount (the standard writable data/rootfs partition on embedded, automotive and IoT devices) can drive `ubi_eba_unmap_leb()` through the UBIFS journal and background thread; the direct ioctl path has no capability check either, only `FMODE_WRITE` on the volume node.\nUI:N - Exploitation needs only the attacker's own file I/O or ioctls against an already-mounted UBI/UBIFS volume; no victim action, mount of attacker-supplied media, or administrator interaction is required.\nS:U - The hang and the freed-slab-object corruption are confined to the kernel's own security authority on the affected host, with no crossing of a VM, IOMMU, or sandbox boundary.\nC:H - The use-after-free on the `ubi_wl_entry_slab` object lets the attacker read fields (`e->pnum`, `e->ec`, rbtree links) out of memory that has been freed and can be reallocated with attacker-groomed content, giving a path to kernel memory disclosure.\nI:H - `rb_erase(&e->u.rb, &ubi->used)` and the subsequent `schedule_erase()` operate on the freed entry, writing rbtree pointer values through a dangling object and re-queuing it — a classic UAF write primitive usable for heap corruption and control-flow hijack.\nA:H - The `goto retry` loop never terminates, pinning a CPU at 100% in an unkillable kernel thread while holding `ubi->fm_protect` and the LEB write lock, which permanently hangs all I/O to the UBI device and its UBIFS filesystems until reboot; the concurrent UAF independently causes kernel crashes." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/mtd/ubi/wl.c" ], "versions": [ { "version": "43f9b25a9cdd7b177f77f026b1461abd1abbd174", "lessThan": "b40d2fbf47af58377e898b5062077a47bb28a132", "status": "affected", "versionType": "git" }, { "version": "43f9b25a9cdd7b177f77f026b1461abd1abbd174", "lessThan": "f006f596fe851c3b6aae60b79f89f89f0e515d2f", "status": "affected", "versionType": "git" }, { "version": "43f9b25a9cdd7b177f77f026b1461abd1abbd174", "lessThan": "b5be23f6ae610bdb262160a1f294afee6d0e6a69", "status": "affected", "versionType": "git" }, { "version": "43f9b25a9cdd7b177f77f026b1461abd1abbd174", "lessThan": "8a18856e074479bd050b01e688c58defadce7ab0", "status": "affected", "versionType": "git" }, { "version": "43f9b25a9cdd7b177f77f026b1461abd1abbd174", "lessThan": "3afaaf6f5867dc4ad383808d4053f428ec7b867d", "status": "affected", "versionType": "git" }, { "version": "43f9b25a9cdd7b177f77f026b1461abd1abbd174", "lessThan": "cc4bc532acda66189bddc03b3fe1ad689d9a48a2", "status": "affected", "versionType": "git" }, { "version": "43f9b25a9cdd7b177f77f026b1461abd1abbd174", "lessThan": "5af1c643184a5d09ff5b3f334077a4d0a163c677", "status": "affected", "versionType": "git" }, { "version": "43f9b25a9cdd7b177f77f026b1461abd1abbd174", "lessThan": "4d57a7333e26040f2b583983e1970d9d460e56b0", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/mtd/ubi/wl.c" ], "versions": [ { "version": "2.6.25", "status": "affected" }, { "version": "0", "lessThan": "2.6.25", "status": "unaffected", "versionType": "semver" }, { "version": "4.14.308", "lessThanOrEqual": "4.14.*", "status": "unaffected", "versionType": "semver" }, { "version": "4.19.276", "lessThanOrEqual": "4.19.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.4.235", "lessThanOrEqual": "5.4.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.173", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.100", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.18", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.2.5", "lessThanOrEqual": "6.2.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.3", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.25", "versionEndExcluding": "4.14.308" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.25", "versionEndExcluding": "4.19.276" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.25", "versionEndExcluding": "5.4.235" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.25", "versionEndExcluding": "5.10.173" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.25", "versionEndExcluding": "5.15.100" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.25", "versionEndExcluding": "6.1.18" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.25", "versionEndExcluding": "6.2.5" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.25", "versionEndExcluding": "6.3" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/b40d2fbf47af58377e898b5062077a47bb28a132" }, { "url": "https://git.kernel.org/stable/c/f006f596fe851c3b6aae60b79f89f89f0e515d2f" }, { "url": "https://git.kernel.org/stable/c/b5be23f6ae610bdb262160a1f294afee6d0e6a69" }, { "url": "https://git.kernel.org/stable/c/8a18856e074479bd050b01e688c58defadce7ab0" }, { "url": "https://git.kernel.org/stable/c/3afaaf6f5867dc4ad383808d4053f428ec7b867d" }, { "url": "https://git.kernel.org/stable/c/cc4bc532acda66189bddc03b3fe1ad689d9a48a2" }, { "url": "https://git.kernel.org/stable/c/5af1c643184a5d09ff5b3f334077a4d0a163c677" }, { "url": "https://git.kernel.org/stable/c/4d57a7333e26040f2b583983e1970d9d460e56b0" } ], "title": "ubi: ubi_wl_put_peb: Fix infinite loop when wear-leveling work failed", "x_generator": { "engine": "bippy-1.2.0" } } } }