{"id":"CVE-2026-80652","title":"crypto: ccp - Treat zero-length cert chain as query for blob lengths","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\ncrypto: ccp - Treat zero-length cert chain as query for blob lengths\n\nWhen handling a PDH export, treat a zero-length userspace cert chain buffer\nas a request to query …","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 76a2b524a4b1d6dc0f2421f9854a01d55d5e5436 < 1c587f30c6242cc37b3d6ee6d91daef84e51633f","Linux >= 76a2b524a4b1d6dc0f2421f9854a01d55d5e5436 < 13b4d5e055d344e34b864bced0a591ceaac7ad81","Linux >= 76a2b524a4b1d6dc0f2421f9854a01d55d5e5436 < 94344bc7c9d70b04be718d841b92873aa3ea8191","Linux >= 76a2b524a4b1d6dc0f2421f9854a01d55d5e5436 < 50c3c7df4f26d36b30bc950a7d780f7029fd52f8","Linux >= 76a2b524a4b1d6dc0f2421f9854a01d55d5e5436 < ee717e73ab47253c82c134c342e32fcdfcfccd87","Linux >= 76a2b524a4b1d6dc0f2421f9854a01d55d5e5436 < 21650fe221ea9b72809140b691589dde8bff3eab","Linux >= 76a2b524a4b1d6dc0f2421f9854a01d55d5e5436 < d88071a6ce091272726bedda26c105b85b23705f","Linux >= 76a2b524a4b1d6dc0f2421f9854a01d55d5e5436 < ef8c9dacda2871accd64e3eda951fef6b788b1ea","Linux 4.16"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-11-06T17:02:28.395791Z"},"published":"2026-08-28","updated":"2026-11-06","sourceUpdated":"2026-11-06T17:05:52.513Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-80652","references":[{"url":"https://git.kernel.org/stable/c/1c587f30c6242cc37b3d6ee6d91daef84e51633f"},{"url":"https://git.kernel.org/stable/c/13b4d5e055d344e34b864bced0a591ceaac7ad81"},{"url":"https://git.kernel.org/stable/c/94344bc7c9d70b04be718d841b92873aa3ea8191"},{"url":"https://git.kernel.org/stable/c/50c3c7df4f26d36b30bc950a7d780f7029fd52f8"},{"url":"https://git.kernel.org/stable/c/ee717e73ab47253c82c134c342e32fcdfcfccd87"},{"url":"https://git.kernel.org/stable/c/21650fe221ea9b72809140b691589dde8bff3eab"},{"url":"https://git.kernel.org/stable/c/d88071a6ce091272726bedda26c105b85b23705f"},{"url":"https://git.kernel.org/stable/c/ef8c9dacda2871accd64e3eda951fef6b788b1ea"}],"tags":["cve.org"],"epss":0.0022,"epssPercentile":0.1255,"ingestedAt":"2026-11-06T18:00:12.538Z","slug":"CVE-2026-80652","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\ncrypto: ccp - Treat zero-length cert chain as query for blob lengths\n\nWhen handling a PDH export, treat a zero-length userspace cert chain buffer\nas a request to query the length of the relevant blobs.  Failure to account\nfor the zero-length buffer trips a BUG_ON() when running with\nCONFIG_DEBUG_VIRTUAL=y due to trying to get the physical address of the\nZERO_SIZE_PTR (returned by kzalloc() on the bogus allocation).\n\n   kernel BUG at arch/x86/mm/physaddr.c:28 !\n  Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI\n  CPU: 30 UID: 0 PID: 28580 Comm: syz.2.18 Kdump: loaded\n  Tainted: G        W           6.18.16-smp-DEV #1 NONE\n  Tainted: [W]=WARN\n  Hardware name: Google, Inc. Arcadia_IT_80/Arcadia_IT_80, BIOS 12.62.0-0 11/19/2025\n   RIP: 0010:__phys_addr+0x16a/0x180 arch/x86/mm/physaddr.c:28\n  RSP: 0018:ffffc9008329fc80 EFLAGS: 00010293\n  RAX: ffffffff8179110a RBX: 0000778000000010 RCX: ffff8884e6992600\n  RDX: 0000000000000000 RSI: 0000000080000010 RDI: 0000778000000010\n  RBP: ffffc9008329fdf0 R08: 0000000000000dc0 R09: 00000000ffffffff\n  R10: dffffc0000000000 R11: fffffbfff126d297 R12: dffffc0000000000\n  R13: 1ffff92010653fc8 R14: 0000000080000010 R15: dffffc0000000000\n  FS:  0000555556bec9c0(0000) GS:ffff88aa4ce1c000(0000) knlGS:0000000000000000\n  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n  CR2: 00007fd3159e7000 CR3: 00000004fbc44000 CR4: 0000000000350ef0\n  Call Trace:\n   <TASK>\n    [<ffffffff853d3869>] sev_ioctl_do_pdh_export+0x559/0x7a0 drivers/crypto/ccp/sev-dev.c:2308\n    [<ffffffff853d1fdd>] sev_ioctl+0x2cd/0x480 drivers/crypto/ccp/sev-dev.c:2556\n    [<ffffffff82549ebc>] vfs_ioctl fs/ioctl.c:52 [inline]\n    [<ffffffff82549ebc>] __do_sys_ioctl fs/ioctl.c:598 [inline]\n    [<ffffffff82549ebc>] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:584\n    [<ffffffff8630115f>] do_syscall_x64 arch/x86/entry/syscall_64.c:64 [inline]\n    [<ffffffff8630115f>] do_syscall_64+0x9f/0xf40 arch/x86/entry/syscall_64.c:98\n   [<ffffffff81000136>] entry_SYSCALL_64_after_hwframe+0x76/0x7e\n  RIP: 0033:0x7fd3158eac39\n   </TASK>\n\nThankfully, the bug is benign outside of CONFIG_DEBUG_VIRTUAL=y as getting\nthe physical address is just arithmetic, and the PSP errors out before\ntrying to write to the garbage address (which it must, otherwise querying\nthe blob lengths would clobber memory at pfn=0).\n\n## Affected\n\n- `Linux >= 76a2b524a4b1d6dc0f2421f9854a01d55d5e5436 < 1c587f30c6242cc37b3d6ee6d91daef84e51633f`\n- `Linux >= 76a2b524a4b1d6dc0f2421f9854a01d55d5e5436 < 13b4d5e055d344e34b864bced0a591ceaac7ad81`\n- `Linux >= 76a2b524a4b1d6dc0f2421f9854a01d55d5e5436 < 94344bc7c9d70b04be718d841b92873aa3ea8191`\n- `Linux >= 76a2b524a4b1d6dc0f2421f9854a01d55d5e5436 < 50c3c7df4f26d36b30bc950a7d780f7029fd52f8`\n- `Linux >= 76a2b524a4b1d6dc0f2421f9854a01d55d5e5436 < ee717e73ab47253c82c134c342e32fcdfcfccd87`\n- `Linux >= 76a2b524a4b1d6dc0f2421f9854a01d55d5e5436 < 21650fe221ea9b72809140b691589dde8bff3eab`\n- `Linux >= 76a2b524a4b1d6dc0f2421f9854a01d55d5e5436 < d88071a6ce091272726bedda26c105b85b23705f`\n- `Linux >= 76a2b524a4b1d6dc0f2421f9854a01d55d5e5436 < ef8c9dacda2871accd64e3eda951fef6b788b1ea`\n- `Linux 4.16`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}