Tracker / CVE-2026-64324
CVE-2026-64324
In the Linux kernel, the following vulnerability has been resolved: udf: validate free block extents against the partition length udf_free_blocks() checks the logical block number and count against the partition length, but drops the extent offset from that final bound. A crafted extent can pass the guard while logicalBlockNum + offset + count points past the partition, which later indexes past the space bitmap array. A single ftruncate(2) on a file backed by such an extent reliably panics the kernel. This is a local availability issue. On desktop systems where UDisks/polkit allows the active user to mount removable UDF media without CAP_SYS_ADMIN, an unprivileged local user can supply the crafted filesystem and trigger the panic by truncating a writable file on it. Systems that require root or CAP_SYS_ADMIN to mount the image have a higher prerequisite. No confidentiality or integrity impact is claimed: the reproduced primitive is an out-of-bounds read of a bitmap pointer slot followed by a kernel panic. Use the already computed logicalBlockNum + offset + count value for the partition length check. Also make load_block_bitmap() reject an out-of-range block group before indexing s_block_bitmap[], so corrupted callers cannot walk past the flexible array.
Affected products and versions
| linux | linux_kernel · 4.19.320 → 4.20 |
|---|---|
| linux | linux_kernel · 5.10.224 → 5.10.261 |
| linux | linux_kernel · 5.15.165 → 5.15.212 |
| linux | linux_kernel · 5.4.282 → 5.5 |
| linux | linux_kernel · 6.1.105 → 6.1.178 |
| linux | linux_kernel · 6.10.5 → 6.12.96 |
| linux | linux_kernel · 6.13 → 6.18.39 |
| linux | linux_kernel · 6.19 → 7.1.4 |
| linux | linux_kernel · 6.6.46 → 6.6.145 |