{"id":"CVE-2026-89741","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-89741","summary":"Revert \"media: v4l2-dev: fix error handling in __video_register_device()\"","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nRevert \"media: v4l2-dev: fix error handling in __video_register_device()\"\n\nThis reverts commit 2a934fdb01db6458288fc9386d3d8ceba6dd551a.\n\nThe intentions of that patch were good, but it doesn't work.\n\nThe idea is that if device_register fails, you have to do a put_device\nto let the ref counter release resources.\n\nHowever, the V4L2 API says that if video_register_device() fails, then\nyou have to call video_device_release(), which kfree()s the video_device\nstruct.\n\nBut the put_device() will already have freed the struct, so you end\nup in a double-free scenario.\n\nThere is not really a good way of fixing this without breaking\nvideo_register_device() into two parts, one that initializes everything,\nand one that does the actual device_register, and then converting all\nV4L2 drivers to this new model.\n\nThat is a massive job, and it is very unlikely that device_register\nwill fail.\n\nSo rather than ending up in a double-free scenario, just revert this\npatch, and in that case we'll have a small memory leak. Which is a lot\nmore robust.","published":"2026-09-11T19:46:47.877Z","modified":"2026-09-14T03:46:30.209664039Z","cvss":{"score":7.8,"severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[{"ecosystem":"Linux","name":"Kernel","fixedVersion":"6.12.109"}],"fix":null,"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/712ca1cf756de2557a116e0df55791bac0c9f99e"},{"type":"WEB","url":"https://git.kernel.org/stable/c/aad08b5f67d2a8116e1a00bce2611c1513b10bce"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ce792b94e03882108019ba996c1a7c4d4e09be2c"},{"type":"WEB","url":"https://git.kernel.org/stable/c/e7600f5cee5de14065f950807931d6e6d40fb2d7"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89741.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89741"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-09-14T03:46:30.209664039Z"}}