CVE-2026-64323
Description
In the Linux kernel, the following vulnerability has been resolved: udf: validate VAT header length against the VAT inode size udf_load_vat() takes the virtual partition's start offset straight from the on-disk VAT 2.0 header without checking it against the VAT inode size: map->s_type_specific.s_virtual.s_start_offset = le16_to_cpu(vat20->lengthHeader); map->s_type_specific.s_virtual.s_num_entries = (sbi->s_vat_inode->i_size - map->s_type_specific.s_virtual.s_start_offset) >> 2; lengthHeader is a fully attacker-controlled 16-bit value. If it exceeds the VAT inode size, the s_num_entries subtraction underflows to a huge count, which defeats the "block > s_num_entries" bound in udf_get_pblock_virt15(); and on the ICB-inline path that function reads ((__le32 *)(iinfo->i_data + s_start_offset))[block] so a large s_start_offset indexes past the inode's in-ICB data. Mounting a crafted UDF image with a virtual (VAT) partition then triggers an out-of-bounds read. Reject a VAT whose header length does not leave room for at least one entry within the VAT inode.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or โ if you've already worked around this in production โ publish your fix to the community-verified tier.
โ Propose a mitigation on Community โ Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
References
- https://git.kernel.org/stable/c/0ad2d09a8d66fa8dc6f9b70d660b5fb4478ea934
- https://git.kernel.org/stable/c/883962731420ec271ed8c1cd76524f4b17faa982
- https://git.kernel.org/stable/c/2900e02a0dd4fc30ac9840e7ce4ca0b041ab0d63
- https://git.kernel.org/stable/c/bb0d384c1f42a5b7ace0bd88fee80b9bb1d49acb
- https://git.kernel.org/stable/c/55287a3555ff0515b3aff181d2c08c0462a41709
- https://git.kernel.org/stable/c/e610fb113cdfa8bf4247c9bf4f2337b81ad4ddad
- https://git.kernel.org/stable/c/74580fdf022909e184223cacc364feb826982d96
- https://git.kernel.org/stable/c/d8202786b3d75125c84ebc4de6d946f92fde0ee8
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.