{"id":"CVE-2026-23121","title":"mISDN: annotate data-race around dev->work","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nmISDN: annotate data-race around dev->work\n\ndev->work can re read locklessly in mISDN_read()\nand mISDN_poll(). Add READ_ONCE()/WRITE_ONCE() annotations.\n\nBUG: KCSAN: da…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 1b2b03f8e514e4f68e293846ba511a948b80243c < d5d99cb9e0839093cd53aa3b28176fce2f820ca0","Linux >= 1b2b03f8e514e4f68e293846ba511a948b80243c < 13f3b3b87068898056db4c79ee67052fbde11d43","Linux >= 1b2b03f8e514e4f68e293846ba511a948b80243c < accc3f8266d2a49881dbcf78c459477f4efa0ff3","Linux >= 1b2b03f8e514e4f68e293846ba511a948b80243c < fc8ba17fd3337bd8b1913c30b95df0fee00d8fb7","Linux >= 1b2b03f8e514e4f68e293846ba511a948b80243c < aa6e33cd74ca4965f2bbcb025e0b672fb0168a69","Linux >= 1b2b03f8e514e4f68e293846ba511a948b80243c < 7ac345a93af31358e18e9606eb7b354691bf6757","Linux >= 1b2b03f8e514e4f68e293846ba511a948b80243c < 8175dbf174d487afab81e936a862a8d9b8a1ccb6","Linux 2.6.27"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-06-10T20:40:15.361866Z"},"published":"2026-02-14","updated":"2026-10-19","sourceUpdated":"2026-10-19T18:25:32.103Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-23121","references":[{"url":"https://git.kernel.org/stable/c/d5d99cb9e0839093cd53aa3b28176fce2f820ca0"},{"url":"https://git.kernel.org/stable/c/13f3b3b87068898056db4c79ee67052fbde11d43"},{"url":"https://git.kernel.org/stable/c/accc3f8266d2a49881dbcf78c459477f4efa0ff3"},{"url":"https://git.kernel.org/stable/c/fc8ba17fd3337bd8b1913c30b95df0fee00d8fb7"},{"url":"https://git.kernel.org/stable/c/aa6e33cd74ca4965f2bbcb025e0b672fb0168a69"},{"url":"https://git.kernel.org/stable/c/7ac345a93af31358e18e9606eb7b354691bf6757"},{"url":"https://git.kernel.org/stable/c/8175dbf174d487afab81e936a862a8d9b8a1ccb6"}],"tags":["cve.org"],"epss":0.0014,"epssPercentile":0.02972,"ingestedAt":"2026-10-19T18:35:50.101Z","slug":"CVE-2026-23121","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nmISDN: annotate data-race around dev->work\n\ndev->work can re read locklessly in mISDN_read()\nand mISDN_poll(). Add READ_ONCE()/WRITE_ONCE() annotations.\n\nBUG: KCSAN: data-race in mISDN_ioctl / mISDN_read\n\nwrite to 0xffff88812d848280 of 4 bytes by task 10864 on cpu 1:\n  misdn_add_timer drivers/isdn/mISDN/timerdev.c:175 [inline]\n  mISDN_ioctl+0x2fb/0x550 drivers/isdn/mISDN/timerdev.c:233\n  vfs_ioctl fs/ioctl.c:51 [inline]\n  __do_sys_ioctl fs/ioctl.c:597 [inline]\n  __se_sys_ioctl+0xce/0x140 fs/ioctl.c:583\n  __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:583\n  x64_sys_call+0x14b0/0x3000 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+0xd8/0x2c0 arch/x86/entry/syscall_64.c:94\n entry_SYSCALL_64_after_hwframe+0x77/0x7f\n\nread to 0xffff88812d848280 of 4 bytes by task 10857 on cpu 0:\n  mISDN_read+0x1f2/0x470 drivers/isdn/mISDN/timerdev.c:112\n  do_loop_readv_writev fs/read_write.c:847 [inline]\n  vfs_readv+0x3fb/0x690 fs/read_write.c:1020\n  do_readv+0xe7/0x210 fs/read_write.c:1080\n  __do_sys_readv fs/read_write.c:1165 [inline]\n  __se_sys_readv fs/read_write.c:1162 [inline]\n  __x64_sys_readv+0x45/0x50 fs/read_write.c:1162\n  x64_sys_call+0x2831/0x3000 arch/x86/include/generated/asm/syscalls_64.h:20\n  do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]\n  do_syscall_64+0xd8/0x2c0 arch/x86/entry/syscall_64.c:94\n entry_SYSCALL_64_after_hwframe+0x77/0x7f\n\nvalue changed: 0x00000000 -> 0x00000001\n\n## Affected\n\n- `Linux >= 1b2b03f8e514e4f68e293846ba511a948b80243c < d5d99cb9e0839093cd53aa3b28176fce2f820ca0`\n- `Linux >= 1b2b03f8e514e4f68e293846ba511a948b80243c < 13f3b3b87068898056db4c79ee67052fbde11d43`\n- `Linux >= 1b2b03f8e514e4f68e293846ba511a948b80243c < accc3f8266d2a49881dbcf78c459477f4efa0ff3`\n- `Linux >= 1b2b03f8e514e4f68e293846ba511a948b80243c < fc8ba17fd3337bd8b1913c30b95df0fee00d8fb7`\n- `Linux >= 1b2b03f8e514e4f68e293846ba511a948b80243c < aa6e33cd74ca4965f2bbcb025e0b672fb0168a69`\n- `Linux >= 1b2b03f8e514e4f68e293846ba511a948b80243c < 7ac345a93af31358e18e9606eb7b354691bf6757`\n- `Linux >= 1b2b03f8e514e4f68e293846ba511a948b80243c < 8175dbf174d487afab81e936a862a8d9b8a1ccb6`\n- `Linux 2.6.27`\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":[]}