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CVE-2025-21671 is a use-after-free vulnerability in the Linux kernel zram driver. On an early failure path in zram_meta_alloc, the driver frees the allocated zram table but does not clear the associated pointer. If a failed, uninitialized zram device is subsequently reset, zram_meta_free can dereference the stale pointer and access freed memory.
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Linux kernel zram use-after-free vulnerability.
Linux kernel zram table use-after-free vulnerability.
A use-after-free vulnerability in the Linux kernel zram component. An early zram_meta_alloc failure can free zram->table without nulling the pointer, potentially allowing zram_meta_free to access freed memory when a failed, uninitialized device is reset.
A Linux kernel zram use-after-free vulnerability (CWE-416) caused by failure to NULL the zram table pointer after freeing it during an early metadata-allocation failure. Resetting an uninitialized failed zram device can access freed memory.
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Cross-references every affected SKU, including bundled OEM variants.
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