{"id":"CVE-2026-43484","state":"PUBLISHED","title":"mmc: core: Avoid bitfield RMW for claim/retune flags","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nmmc: core: Avoid bitfield RMW for claim/retune flags\n\nMove claimed and retune control flags out of the bitfield word to\navoid unrelated RMW side effects in asynchronous contexts.\n\nThe host->claimed bit shared a word with retune flags. Writes to claimed\nin __mmc_claim_host() or retune_now in mmc_mq_queue_rq() can overwrite\nother bits when concurrent updates happen in other contexts, triggering\nspurious WARN_ON(!host->claimed). Convert claimed, can_retune,\nretune_now and retune_paused to bool to remove shared-word coupling.","publishedAt":"2026-05-13T15:08:30.919Z","updatedAt":"2026-05-13T15:08:30.919Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"6c0cedd1ef9527ef13e66875746570e76a3188a7","status":"affected","lessThan":"41dce4dae583a8ce06a7ebf4ce704c46a142957c","versionType":"git"},{"version":"6c0cedd1ef9527ef13e66875746570e76a3188a7","status":"affected","lessThan":"bb7fc2498c3bb25fa6a91f22f4760005325cfbd5","versionType":"git"},{"version":"6c0cedd1ef9527ef13e66875746570e76a3188a7","status":"affected","lessThan":"270277c2ab631044867adb1bd2f2433d3892de6e","versionType":"git"},{"version":"6c0cedd1ef9527ef13e66875746570e76a3188a7","status":"affected","lessThan":"45038e03f15e992c48603fff8c6b1c9be5397ac9","versionType":"git"},{"version":"6c0cedd1ef9527ef13e66875746570e76a3188a7","status":"affected","lessThan":"0e06cc511c61cff1591e5435a207759adcc76b6d","versionType":"git"},{"version":"6c0cedd1ef9527ef13e66875746570e76a3188a7","status":"affected","lessThan":"d3a3caf44c8ec26f5d63dc17c1c7242effa60ebc","versionType":"git"},{"version":"6c0cedd1ef9527ef13e66875746570e76a3188a7","status":"affected","lessThan":"901084c51a0a8fb42a3f37d2e9c62083c495f824","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["include/linux/mmc/host.h"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"4.15","status":"affected"},{"version":"0","status":"unaffected","lessThan":"4.15","versionType":"semver"},{"version":"5.15.203","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.167","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.130","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.78","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.19","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"6.19.9","status":"unaffected","lessThanOrEqual":"6.19.*","versionType":"semver"},{"version":"7.0","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["include/linux/mmc/host.h"]}],"references":["https://git.kernel.org/stable/c/41dce4dae583a8ce06a7ebf4ce704c46a142957c","https://git.kernel.org/stable/c/bb7fc2498c3bb25fa6a91f22f4760005325cfbd5","https://git.kernel.org/stable/c/270277c2ab631044867adb1bd2f2433d3892de6e","https://git.kernel.org/stable/c/45038e03f15e992c48603fff8c6b1c9be5397ac9","https://git.kernel.org/stable/c/0e06cc511c61cff1591e5435a207759adcc76b6d","https://git.kernel.org/stable/c/d3a3caf44c8ec26f5d63dc17c1c7242effa60ebc","https://git.kernel.org/stable/c/901084c51a0a8fb42a3f37d2e9c62083c495f824"],"weaknesses":[],"ingestedAt":"2026-10-29T20:11:57.932Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/43xxx/CVE-2026-43484.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-43484","state":"PUBLISHED","datePublished":"2026-05-13T15:08:30.919Z","dateUpdated":"2026-05-13T15:08:30.919Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-05-01T14:12:56.012Z"},"containers":{"cna":{"title":"mmc: core: Avoid bitfield RMW for claim/retune flags","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nmmc: core: Avoid bitfield RMW for claim/retune flags\n\nMove claimed and retune control flags out of the bitfield word to\navoid unrelated RMW side effects in asynchronous contexts.\n\nThe host->claimed bit shared a word with retune flags. Writes to claimed\nin __mmc_claim_host() or retune_now in mmc_mq_queue_rq() can overwrite\nother bits when concurrent updates happen in other contexts, triggering\nspurious WARN_ON(!host->claimed). Convert claimed, can_retune,\nretune_now and retune_paused to bool to remove shared-word coupling."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"6c0cedd1ef9527ef13e66875746570e76a3188a7","status":"affected","lessThan":"41dce4dae583a8ce06a7ebf4ce704c46a142957c","versionType":"git"},{"version":"6c0cedd1ef9527ef13e66875746570e76a3188a7","status":"affected","lessThan":"bb7fc2498c3bb25fa6a91f22f4760005325cfbd5","versionType":"git"},{"version":"6c0cedd1ef9527ef13e66875746570e76a3188a7","status":"affected","lessThan":"270277c2ab631044867adb1bd2f2433d3892de6e","versionType":"git"},{"version":"6c0cedd1ef9527ef13e66875746570e76a3188a7","status":"affected","lessThan":"45038e03f15e992c48603fff8c6b1c9be5397ac9","versionType":"git"},{"version":"6c0cedd1ef9527ef13e66875746570e76a3188a7","status":"affected","lessThan":"0e06cc511c61cff1591e5435a207759adcc76b6d","versionType":"git"},{"version":"6c0cedd1ef9527ef13e66875746570e76a3188a7","status":"affected","lessThan":"d3a3caf44c8ec26f5d63dc17c1c7242effa60ebc","versionType":"git"},{"version":"6c0cedd1ef9527ef13e66875746570e76a3188a7","status":"affected","lessThan":"901084c51a0a8fb42a3f37d2e9c62083c495f824","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["include/linux/mmc/host.h"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"4.15","status":"affected"},{"version":"0","status":"unaffected","lessThan":"4.15","versionType":"semver"},{"version":"5.15.203","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.167","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.130","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.78","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.19","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"6.19.9","status":"unaffected","lessThanOrEqual":"6.19.*","versionType":"semver"},{"version":"7.0","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["include/linux/mmc/host.h"]}],"references":[{"url":"https://git.kernel.org/stable/c/41dce4dae583a8ce06a7ebf4ce704c46a142957c"},{"url":"https://git.kernel.org/stable/c/bb7fc2498c3bb25fa6a91f22f4760005325cfbd5"},{"url":"https://git.kernel.org/stable/c/270277c2ab631044867adb1bd2f2433d3892de6e"},{"url":"https://git.kernel.org/stable/c/45038e03f15e992c48603fff8c6b1c9be5397ac9"},{"url":"https://git.kernel.org/stable/c/0e06cc511c61cff1591e5435a207759adcc76b6d"},{"url":"https://git.kernel.org/stable/c/d3a3caf44c8ec26f5d63dc17c1c7242effa60ebc"},{"url":"https://git.kernel.org/stable/c/901084c51a0a8fb42a3f37d2e9c62083c495f824"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-05-13T15:08:30.919Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.15","versionEndExcluding":"5.15.203"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.15","versionEndExcluding":"6.1.167"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.15","versionEndExcluding":"6.6.130"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.15","versionEndExcluding":"6.12.78"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.15","versionEndExcluding":"6.18.19"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.15","versionEndExcluding":"6.19.9"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.15","versionEndExcluding":"7.0"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}