{"id":"CVE-2022-50274","state":"PUBLISHED","title":"media: dvbdev: adopts refcnt to avoid UAF","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nmedia: dvbdev: adopts refcnt to avoid UAF\n\ndvb_unregister_device() is known that prone to use-after-free.\nThat is, the cleanup from dvb_unregister_device() releases the dvb_device\neven if there are pointers stored in file->private_data still refer to it.\n\nThis patch adds a reference counter into struct dvb_device and delays its\ndeallocation until no pointer refers to the object.","publishedAt":"2025-09-15T14:21:10.383Z","updatedAt":"2026-08-05T08:58:01.283Z","severity":{"score":7.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"ac521bbe3d00fa574e66a9361763f2b37725bc97","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"219b44bf94203bd433aa91b7796475bf656348e5","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"6d18b44bb44e1f4d97dfe0efe92ac0f0984739c2","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"2abd73433872194bccdf1432a0980e4ec5273c2a","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"88a6f8a72d167294c0931c7874941bf37a41b6dd","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"a2f0a08aa613176c9688c81d7b598a7779974991","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"9945d05d6693710574f354c5dbddc47f5101eb77","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"0fc044b2b5e2d05a1fa1fb0d7f270367a7855d79","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/media/dvb-core/dvb_ca_en50221.c","drivers/media/dvb-core/dvb_frontend.c","drivers/media/dvb-core/dvbdev.c","include/media/dvbdev.h"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"2.6.12","status":"affected"},{"version":"0","status":"unaffected","lessThan":"2.6.12","versionType":"semver"},{"version":"4.14.303","status":"unaffected","lessThanOrEqual":"4.14.*","versionType":"semver"},{"version":"4.19.270","status":"unaffected","lessThanOrEqual":"4.19.*","versionType":"semver"},{"version":"5.4.229","status":"unaffected","lessThanOrEqual":"5.4.*","versionType":"semver"},{"version":"5.10.163","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.86","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.0.16","status":"unaffected","lessThanOrEqual":"6.0.*","versionType":"semver"},{"version":"6.1.2","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/media/dvb-core/dvb_ca_en50221.c","drivers/media/dvb-core/dvb_frontend.c","drivers/media/dvb-core/dvbdev.c","include/media/dvbdev.h"]}],"references":["https://git.kernel.org/stable/c/ac521bbe3d00fa574e66a9361763f2b37725bc97","https://git.kernel.org/stable/c/219b44bf94203bd433aa91b7796475bf656348e5","https://git.kernel.org/stable/c/6d18b44bb44e1f4d97dfe0efe92ac0f0984739c2","https://git.kernel.org/stable/c/2abd73433872194bccdf1432a0980e4ec5273c2a","https://git.kernel.org/stable/c/88a6f8a72d167294c0931c7874941bf37a41b6dd","https://git.kernel.org/stable/c/a2f0a08aa613176c9688c81d7b598a7779974991","https://git.kernel.org/stable/c/9945d05d6693710574f354c5dbddc47f5101eb77","https://git.kernel.org/stable/c/0fc044b2b5e2d05a1fa1fb0d7f270367a7855d79"],"weaknesses":[],"ingestedAt":"2026-10-29T20:05:26.763Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2022/50xxx/CVE-2022-50274.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2022-50274","state":"PUBLISHED","datePublished":"2025-09-15T14:21:10.383Z","dateUpdated":"2026-08-05T08:58:01.283Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2025-09-15T13:58:00.975Z"},"containers":{"cna":{"title":"media: dvbdev: adopts refcnt to avoid UAF","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nmedia: dvbdev: adopts refcnt to avoid UAF\n\ndvb_unregister_device() is known that prone to use-after-free.\nThat is, the cleanup from dvb_unregister_device() releases the dvb_device\neven if there are pointers stored in file->private_data still refer to it.\n\nThis patch adds a reference counter into struct dvb_device and delays its\ndeallocation until no pointer refers to the object."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"ac521bbe3d00fa574e66a9361763f2b37725bc97","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"219b44bf94203bd433aa91b7796475bf656348e5","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"6d18b44bb44e1f4d97dfe0efe92ac0f0984739c2","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"2abd73433872194bccdf1432a0980e4ec5273c2a","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"88a6f8a72d167294c0931c7874941bf37a41b6dd","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"a2f0a08aa613176c9688c81d7b598a7779974991","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"9945d05d6693710574f354c5dbddc47f5101eb77","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"0fc044b2b5e2d05a1fa1fb0d7f270367a7855d79","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/media/dvb-core/dvb_ca_en50221.c","drivers/media/dvb-core/dvb_frontend.c","drivers/media/dvb-core/dvbdev.c","include/media/dvbdev.h"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"2.6.12","status":"affected"},{"version":"0","status":"unaffected","lessThan":"2.6.12","versionType":"semver"},{"version":"4.14.303","status":"unaffected","lessThanOrEqual":"4.14.*","versionType":"semver"},{"version":"4.19.270","status":"unaffected","lessThanOrEqual":"4.19.*","versionType":"semver"},{"version":"5.4.229","status":"unaffected","lessThanOrEqual":"5.4.*","versionType":"semver"},{"version":"5.10.163","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.86","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.0.16","status":"unaffected","lessThanOrEqual":"6.0.*","versionType":"semver"},{"version":"6.1.2","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/media/dvb-core/dvb_ca_en50221.c","drivers/media/dvb-core/dvb_frontend.c","drivers/media/dvb-core/dvbdev.c","include/media/dvbdev.h"]}],"references":[{"url":"https://git.kernel.org/stable/c/ac521bbe3d00fa574e66a9361763f2b37725bc97"},{"url":"https://git.kernel.org/stable/c/219b44bf94203bd433aa91b7796475bf656348e5"},{"url":"https://git.kernel.org/stable/c/6d18b44bb44e1f4d97dfe0efe92ac0f0984739c2"},{"url":"https://git.kernel.org/stable/c/2abd73433872194bccdf1432a0980e4ec5273c2a"},{"url":"https://git.kernel.org/stable/c/88a6f8a72d167294c0931c7874941bf37a41b6dd"},{"url":"https://git.kernel.org/stable/c/a2f0a08aa613176c9688c81d7b598a7779974991"},{"url":"https://git.kernel.org/stable/c/9945d05d6693710574f354c5dbddc47f5101eb77"},{"url":"https://git.kernel.org/stable/c/0fc044b2b5e2d05a1fa1fb0d7f270367a7855d79"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - The UAF is reached through local chardev operations on /dev/dvb/adapterX/* (open/ioctl/release). Unregister while an fd remains open is triggered by device teardown (USB/FireWire/PCI DVB hot-unplug or driver removal); this is a local device-node attack path, consistent with related dvbdev UAFs (e.g. CVE-2024-27043).\nAC:L - An attacker who opens a DVB node and then causes or observes device unregister (e.g. unplugging a USB/FireWire DVB adapter they control, or teardown on drivers that call dvb_unregister_device without waiting) reliably leaves file->private_data dangling; no uncontrolled race or rare config is required.\nPR:L - Access requires only an unprivileged local user able to open DVB nodes (udev assigns GROUP=video and TAG=uaccess), not root or init-namespace CAP_SYS_ADMIN.\nUI:N - The attacker can open the device and drive subsequent ioctls/close themselves; no separate victim action is required once they have local access and can induce or time device teardown.\nS:U - Impact is confined to the host kernel's privilege domain (local privilege escalation / memory corruption); there is no VM, IOMMU, or other security-authority boundary crossing.\nC:H - Use-after-free of struct dvb_device via file->private_data enables heap reuse and arbitrary read primitives through subsequent ioctl/release paths (per UAF guidance).\nI:H - The same UAF on a kmalloc object used for ioctl dispatch (dvb_generic_ioctl → dvbdev->kernel_ioctl) enables heap spraying and control-flow/write primitives for code execution.\nA:H - Dereferencing the freed dvb_device on ioctl or release causes kernel oops/crash even without full exploitation; UAF availability impact is High."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-05T08:58:01.283Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"4.14.303"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"4.19.270"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"5.4.229"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"5.10.163"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"5.15.86"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"6.0.16"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"6.1.2"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"6.2"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}