{"cve":"CVE-2023-53487","nvd":{"published":"2025-10-01T12:15:51.637","modified":"2026-06-17T06:45:27.100","status":"Analyzed","description":"In the Linux kernel, the following vulnerability has been resolved:\n\npowerpc/rtas_flash: allow user copy to flash block cache objects\n\nWith hardened usercopy enabled (CONFIG_HARDENED_USERCOPY=y), using the\n/proc/powerpc/rtas/firmware_update interface to prepare a system\nfirmware update yields a BUG():\n\n  kernel BUG at mm/usercopy.c:102!\n  Oops: Exception in kernel mode, sig: 5 [#1]\n  LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries\n  Modules linked in:\n  CPU: 0 PID: 2232 Comm: dd Not tainted 6.5.0-rc3+ #2\n  Hardware name: IBM,8408-E8E POWER8E (raw) 0x4b0201 0xf000004 of:IBM,FW860.50 (SV860_146) hv:phyp pSeries\n  NIP:  c0000000005991d0 LR: c0000000005991cc CTR: 0000000000000000\n  REGS: c0000000148c76a0 TRAP: 0700   Not tainted  (6.5.0-rc3+)\n  MSR:  8000000000029033 <SF,EE,ME,IR,DR,RI,LE>  CR: 24002242  XER: 0000000c\n  CFAR: c0000000001fbd34 IRQMASK: 0\n  [ ... GPRs omitted ... ]\n  NIP usercopy_abort+0xa0/0xb0\n  LR  usercopy_abort+0x9c/0xb0\n  Call Trace:\n    usercopy_abort+0x9c/0xb0 (unreliable)\n    __check_heap_object+0x1b4/0x1d0\n    __check_object_size+0x2d0/0x380\n    rtas_flash_write+0xe4/0x250\n    proc_reg_write+0xfc/0x160\n    vfs_write+0xfc/0x4e0\n    ksys_write+0x90/0x160\n    system_call_exception+0x178/0x320\n    system_call_common+0x160/0x2c4\n\nThe blocks of the firmware image are copied directly from user memory\nto objects allocated from flash_block_cache, so flash_block_cache must\nbe created using kmem_cache_create_usercopy() to mark it safe for user\naccess.\n\n[mpe: Trim and indent oops]","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8},"cwes":[],"references":["https://git.kernel.org/stable/c/0ba7f969be599e21d4b1f1e947593de6515f4996","https://git.kernel.org/stable/c/1d29e21ed09fa668416fa7721e08d451b9903485","https://git.kernel.org/stable/c/4f3175979e62de3b929bfa54a0db4b87d36257a7","https://git.kernel.org/stable/c/6acb8a453388374fafb3c3b37534b675b2aa0ae1","https://git.kernel.org/stable/c/8ef25fb13494e35c6dbe15445c7875fa92bc3e8b"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:11:26.888974865+00:00"},"epss":{"cve":"CVE-2023-53487","score":0.00168,"percentile":0.06137,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}