{"id":"CVE-2026-31596","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-31596","generatedAt":"2026-10-28T04:46:43.722Z","title":"In the Linux kernel, the following vulnerability has been resolved: ocfs2: handle invalid dinode in ocfs2_group_extend [BUG] kernel BUG at fs/ocfs2/resize.c:308!","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nocfs2: handle invalid dinode in ocfs2_group_extend\n\n[BUG]\nkernel BUG at fs/ocfs2/resize.c:308!\nOops: invalid opcode: 0000 [#1] SMP KASAN NOPTI\nRIP: 0010:ocfs2_group_extend+0x10aa/0x1ae0 fs/ocfs2/resize.c:308\nCode: 8b8520ff ffff83f8 860f8580 030000e8 5cc3c1fe\nCall Trace:\n ...\n ocfs2_ioctl+0x175/0x6e0 fs/ocfs2/ioctl.c:869\n vfs_ioctl fs/ioctl.c:51 [inline]\n __do_sys_ioctl fs/ioctl.c:597 [inline]\n __se_sys_ioctl fs/ioctl.c:583 [inline]\n __x64_sys_ioctl+0x197/0x1e0 fs/ioctl.c:583\n x64_sys_call+0x1144/0x26a0 arch/x86/include/generated/asm/syscalls_64.h:17\n do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]\n do_syscall_64+0x93/0xf80 arch/x86/entry/syscall_64.c:94\n entry_SYSCALL_64_after_hwframe+0x76/0x7e\n ...\n\n[CAUSE]\nocfs2_group_extend() assumes that the global bitmap inode block\nreturned from ocfs2_inode_lock() has already been validated and\nBUG_ONs when the signature is not a dinode. That assumption is too\nstrong for crafted filesystems because the JBD2-managed buffer path\ncan bypass structural validation and return an invalid dinode to the\nresize ioctl.\n\n[FIX]\nValidate the dinode explicitly in ocfs2_group_extend(). If the global\nbitmap buffer does not contain a valid dinode, report filesystem\ncorruption with ocfs2_error() and fail the resize operation instead of\ncrashing the kernel.","published":"2026-04-24T15:16:37.000Z","lastModified":"2026-06-17T10:34:03.000Z","status":"Modified","sourceIdentifier":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","cvss":{"version":"3.1","score":5.5,"severity":"MEDIUM","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"},"cwe":[],"affected":["linux/linux kernel"],"epss":{"score":0.00133,"percentile":0.02833,"date":"2026-10-27","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.13%). Track it; it rarely justifies an emergency change on its own."},"changes":[],"references":[{"url":"https://git.kernel.org/stable/c/10fb72c47aac446f12a4ccd962c7daa60cc890a1","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/41c6e9bc3a09539deab43957a3211d902a4818f0","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/4a1c0ddc6e7bcf2e9db0eeaab9340dcfe97f448f","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/6575f9fbf084502b7118a628425bf7866666498d","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/7eafcf507fbd68f3276c00f6c02ef155ad69f79b","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/911b557dd7817460881fd51a03069b539c674d0e","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/b328d8e7c437d0f026ba2c13788af6eae77700f1","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/e384a850a3370d89a7a446cdeccd964bfba2a302","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/fabfa6b81bd386154d7e59f8cd8f760f9e68b48c","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-31596","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}