{"uuid": "7622dfe9-a8e7-4820-9012-43a1a6abe3bc", "vulnerability_lookup_origin": "1a89b78e-f703-45f3-bb86-59eb712668bd", "author": "2a075640-a300-48a4-bb44-bc6130783b9b", "vulnerability": "CVE-2024-57877", "type": "published-proof-of-concept", "source": "https://t.me/DarkWebInformer_CVEAlerts/1318", "content": "\ud83d\udd17 DarkWebInformer.com - Cyber Threat Intelligence\n\ud83d\udccc CVE ID: CVE-2024-57877\n\ud83d\udd39 Description: In the Linux kernel, the following vulnerability has been resolved:\n\narm64: ptrace: fix partial SETREGSET for NT_ARM_POE\n\nCurrently poe_set() doesn't initialize the temporary 'ctrl' variable,\nand a SETREGSET call with a length of zero will leave this\nuninitialized. Consequently an arbitrary value will be written back to\ntarget->thread.por_el0, potentially leaking up to 64 bits of memory from\nthe kernel stack. The read is limited to a specific slot on the stack,\nand the issue does not provide a write mechanism.\n\nFix this by initializing the temporary value before copying the regset\nfrom userspace, as for other regsets (e.g. NT_PRSTATUS, NT_PRFPREG,\nNT_ARM_SYSTEM_CALL). In the case of a zero-length write, the existing\ncontents of POR_EL1 will be retained.\n\nBefore this patch:\n\n| # ./poe-test\n| Attempting to write NT_ARM_POE::por_el0 = 0x900d900d900d900d\n| SETREGSET(nt=0x40f, len=8) wrote 8 bytes\n|\n| Attempting to read NT_ARM_POE::por_el0\n| GETREGSET(nt=0x40f, len=8) read 8 bytes\n| Read NT_ARM_POE::por_el0 = 0x900d900d900d900d\n|\n| Attempting to write NT_ARM_POE (zero length)\n| SETREGSET(nt=0x40f, len=0) wrote 0 bytes\n|\n| Attempting to read NT_ARM_POE::por_el0\n| GETREGSET(nt=0x40f, len=8) read 8 bytes\n| Read NT_ARM_POE::por_el0 = 0xffff8000839c3d50\n\nAfter this patch:\n\n| # ./poe-test\n| Attempting to write NT_ARM_POE::por_el0 = 0x900d900d900d900d\n| SETREGSET(nt=0x40f, len=8) wrote 8 bytes\n|\n| Attempting to read NT_ARM_POE::por_el0\n| GETREGSET(nt=0x40f, len=8) read 8 bytes\n| Read NT_ARM_POE::por_el0 = 0x900d900d900d900d\n|\n| Attempting to write NT_ARM_POE (zero length)\n| SETREGSET(nt=0x40f, len=0) wrote 0 bytes\n|\n| Attempting to read NT_ARM_POE::por_el0\n| GETREGSET(nt=0x40f, len=8) read 8 bytes\n| Read NT_ARM_POE::por_el0 = 0x900d900d900d900d\n\ud83d\udccf Published: 2025-01-11T14:49:03.297Z\n\ud83d\udccf Modified: 2025-01-11T14:49:03.297Z\n\ud83d\udd17 References:\n1. https://git.kernel.org/stable/c/4105dd76bc8ad6529d47157ef0565cb84ca6676c\n2. https://git.kernel.org/stable/c/594bfc4947c4fcabba1318d8384c61a29a6b89fb", "creation_timestamp": "2025-01-11T15:04:31.000000Z"}