{ "schemaVersion": 1, "attribution": [ { "source": "CISA Known Exploited Vulnerabilities", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog", "licence": "US government work" }, { "source": "GitHub Advisory Database", "url": "https://github.com/advisories", "licence": "CC BY 4.0" }, { "source": "Have I Been Pwned", "url": "https://haveibeenpwned.com/", "licence": "CC BY 4.0" }, { "source": "CVE Program (CVE records)", "url": "https://www.cve.org/Legal/TermsOfUse", "licence": "CVE Terms of Use", "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.", "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy." }, { "source": "FIRST EPSS", "url": "https://www.first.org/epss/", "licence": "free to use; FIRST requests attribution" } ], "record": { "id": "CVE-2026-68187", "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-68187", "idYear": 2026, "status": "PUBLISHED", "publishedAt": "2026-08-10T11:59:59.303Z", "updatedAt": "2026-08-19T16:30:56.724Z", "importedAt": "2026-10-24T01:58:25.636Z", "snapshot": { "id": "cve_2026-10-24_midnight_baseline", "at": "2026-10-24T00:00:00.000Z", "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z" }, "facts": { "title": "exec: fix unsigned loop counter wrap in transfer_args_to_stack()", "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nexec: fix unsigned loop counter wrap in transfer_args_to_stack()\n\nThe stop value is derived from bprm->p >> PAGE_SHIFT. The index variable\nis an unsigned long. If bprm->p drops below PAGE_SIZE and stop becomes\nzero the loop condition index >= stop is always true.\n\nAfter the index == 0 iteration the decrement wraps to ULONG_MAX and\nbprm->page[ULONG_MAX] reads sizeof(void *) bytes in front of the array.\nThe pointer has wrapped to -1. That garbage pointer is then passed to\nkmap_local_page() and PAGE_SIZE bytes are copied from wherever that\nlands into the stack of the process being created. And the loop doesn't\nterminate either...\n\nGetting there only requires bprm->p < PAGE_SIZE. On !MMU\nbprm_set_stack_limit() and bprm_hit_stack_limit() are empty. So the only\nconstraint on how far bprm->p is pushed down is valid_arg_len(), i.e.\nthat each individual string still fits in what is left.\n\nbprm->p starts at PAGE_SIZE * MAX_ARG_PAGES - sizeof(void *) so a\nsingle argument or environment string of a little over 31 pages leaves\nit in the first page:\n\n Oops - load access fault [#1]\n CPU: 0 UID: 0 PID: 1 Comm: victim Not tainted 7.2.0-rc4 #1\n epc : __memcpy+0xd4/0xf8\n ra : transfer_args_to_stack+0xaa/0xae\n s4 : ffffffffffffffff s2 : 0000000000000000\n a1 : ffffffdc98000000 a2 : 0000000000001000\n status: 0000000a00001880 badaddr: ffffffdc98000000 cause: 0000000000000005\n [<801a5324>] __memcpy+0xd4/0xf8\n [<800d5f6a>] load_flat_binary+0x43a/0x65e\n [<800a2de4>] bprm_execve+0x1d4/0x316\n [<800a351a>] do_execveat_common+0x12e/0x138\n [<800a3d44>] __riscv_sys_execve+0x38/0x4e\n Kernel panic - not syncing: Fatal exception in interrupt\n\nThis is an arcane bug but we should still fix it.\n\nCount down from MAX_ARG_PAGES so the loop ends when index reaches stop,\nstop == 0 included. The iterations performed are unchanged for every\nother value of stop.\n\nOnly CONFIG_MMU=n builds are affected, transfer_args_to_stack() is used\nby binfmt_flat and binfmt_elf_fdpic on nommu only.\n\nThe loop predates git history. commit 7e7ec6a93434\n(\"elf_fdpic_transfer_args_to_stack(): make it generic\") only moved it\nfrom binfmt_elf_fdpic.c into fs/exec.c and narrowed the copy to the used\npart of the first page. The condition and the decrement are unchanged\nfrom 2.6.12-rc2.", "affected": [ { "vendor": "Linux", "product": "Linux", "defaultStatus": "unaffected", "versions": [ { "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "status": "affected", "versionType": "git", "lessThan": "a9eb5c4949008034909bc34ecfa0843ecc1d0ab3" }, { "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "status": "affected", "versionType": "git", "lessThan": "67cf5cdad823afb0530d6d0341fbf4ca07e93a09" }, { "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "status": "affected", "versionType": "git", "lessThan": "66e20942890a383eb39b2009a2ceb4c2ebec37ef" }, { "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "status": "affected", "versionType": "git", "lessThan": "c62bb00caba66e01fb578d5f0302f247dc64930a" }, { "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "status": "affected", "versionType": "git", "lessThan": "dfc2a00742af4cb7251c1a8fbce4fbae3cc0de4e" }, { "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "status": "affected", "versionType": "git", "lessThan": "2bc6bf70d41055377f390d06f0f3521deb62fd3b" }, { "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "status": "affected", "versionType": "git", "lessThan": "55fa2c7f2b15583d1a2fe1b5abcc24377359339f" }, { "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "status": "affected", "versionType": "git", "lessThan": "16cc4f5c1c4b9e45eca7f7deefa5410a292db599" } ] }, { "vendor": "Linux", "product": "Linux", "defaultStatus": "affected", "versions": [ { "version": "2.6.12", "status": "affected" }, { "version": "0", "status": "unaffected", "versionType": "semver", "lessThan": "2.6.12" }, { "version": "5.10.265", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.10.*" }, { "version": "5.15.216", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.15.*" }, { "version": "6.1.183", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.1.*" }, { "version": "6.6.148", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.6.*" }, { "version": "6.12.101", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.12.*" }, { "version": "6.18.42", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.18.*" }, { "version": "7.1.6", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "7.1.*" }, { "version": "7.2", "status": "unaffected", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*" } ] } ] } } }