Service interruption via lingering card-detect handling
Published Sep 11, 2026 · Updated Sep 11, 2026
Use-after-free in the Linux via-sdmmc driver allows attackers to interrupt service after MMC host registration fails during device probing. The probe error path unmaps registers and frees the host without disabling and freeing the card-detect IRQ or canceling carddet_work, so both callbacks dereference freed host state and MMIO mappings. Reachability requires a VIA SD/MMC controller, a failed mmc_add_host() call, and subsequent card-detect handling; the resulting invalid kernel accesses can crash the system.
Summary
What happened
Use-after-free in the Linux via-sdmmc driver allows attackers to interrupt service after MMC host registration fails during device probing. The probe error path unmaps registers and frees the host without disabling and freeing the card-detect IRQ or canceling carddet_work, so both callbacks dereference freed host state and MMIO mappings. Reachability requires a VIA SD/MMC controller, a failed mmc_add_host() call, and subsequent card-detect handling; the resulting invalid kernel accesses can crash the system.
The record
- CVE
- CVE-2026-89440
- Published
- Sep 11, 2026
- Updated
- Sep 11, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- Unavailable
- Attack vector
- Unavailable
- Privileges
- Unavailable
Timeline
How it unfolded
- Sep 11, 2026CVE publishedPublication date reported by the CVE source.
- Sep 11, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=076bcd2c93e16b05c10564e299d6e5d26a766d00
- Affected versionversion=0959cc1685eb19774300d43ef25e318b457b156b
- Affected versionversion=0ec94795114edc7e24ec71849dce42bfa61dafa3
- Affected versionversion=12b8e81b77c05c658efd9cde3585bbd65ae39b59
- Affected versionversion=4.14.303 <4.15
- Affected versionversion=4.19.270 <4.20
- Affected versionversion=4.9.337 <4.10
- Affected versionversion=5.10.163 <5.11
- Affected versionversion=5.15.86 <5.16
- Affected versionversion=5.4.229 <5.5
- Affected versionversion=6.0.16 <6.1
- Affected versionversion=6.1.2 <6.2
- Affected versionversion=6.2
- Affected versionversion=63400da6cd37a9793c19bb6aed7131b58b975a04
- Affected versionversion=95025a8dd0ec015872f6c16473fe04d6264e68ca
- Affected versionversion=ba91b413983a9235792523c6b9f7ba2586c4d75d
- Affected versionversion=e4e46fb61e3bb4628170810d3f2b996b709b90d9 <088eaa92fcebaa6b957ccf9635afdf39643a577d
- Affected versionversion=e4e46fb61e3bb4628170810d3f2b996b709b90d9 <2550f89589caad7402d618d7dffc038582c94b6b
- Affected versionversion=e4e46fb61e3bb4628170810d3f2b996b709b90d9 <c2b8a624911999399cc14822fec3e35032b3cee4
- Affected versionversion=e4e46fb61e3bb4628170810d3f2b996b709b90d9 <efe7f25dd27e35063477b4b0e7eed3675669fd99
- Affected versionversion=f59ef2a47a228e51322ad76752a55a8917c56e38
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
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Weakness, pattern, technique
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Public exploit references
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Technologies
Your stack
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