DEBIAN-CVE-2025-40307
Record from OSV · Published December 8, 2025
In the Linux kernel, the following vulnerability has been resolved: exfat: validate cluster allocation bits of the allocation bitmap syzbot created an exfat image with cluster bits not set for the allocation bitmap. exfat-fs reads and uses the allocation bitmap without checking this. The problem is that if the start cluster of the allocation bitmap is 6, cluster 6 can be allocated when creating a directory with mkdir. exfat zeros out this cluster in exfat_mkdir, which can delete existing entries. This can reallocate the allocated entries. In addition, the allocation bitmap is also zeroed out, so cluster 6 can be reallocated. This patch adds exfat_test_bitmap_range to validate that clusters used for the allocation bitmap are correctly marked as in-use.
Fixed versions
Upgrade to a fixed version or later. Language registries are listed first, then Linux distributions, then vendor products.
| Package | Ecosystem | Fixed in |
|---|---|---|
| linux | Debian:13 | 6.12.63-1 |
| linux | Debian:14 | 6.17.8-1 |
| linux | Debian:12 | 6.1.187-1 |
Risk scores
Affected products
| Vendor | Product | Versions |
|---|---|---|
| Debian:13 | linux | 6.12.63-1~bpo12+1, 6.12.57-1~bpo12+1, 6.12.57-1 |
| Debian:14 | linux | 6.12.43-1~bpo12+1, 6.12.48-1, 6.12.57-1 |
| Debian:12 | linux | 6.1.128-1, 6.1.129-1, 6.1.133-1 |
Timeline
- Dec 8, 2025 CVE Published
- Oct 16, 2026 CVE Updated
Query this with the API
The same record, from the CLI:
vulnetix vdb vuln DEBIAN-CVE-2025-40307
vulnetix vdb fixes DEBIAN-CVE-2025-40307Or with curl, using the org id and key from your account page:
curl -s -H "Authorization: ApiKey ${VULNETIX_ORG_ID}:${VULNETIX_API_KEY}" \
"https://api.vdb.vulnetix.com/v2/vuln/DEBIAN-CVE-2025-40307/fixes/registry"The Community plan is free and allows 50 queries a day. Get a free API key · API quickstart