CVE-2026-45991
In the Linux kernel, the following vulnerability has been resolved: udf: fix partition descriptor append bookkeeping Mounting a crafted UDF image with repeated partition descriptors can trigger a heap out-of-bounds write in part_descs_loc[].…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.17%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
In the Linux kernel, the following vulnerability has been resolved: udf: fix partition descriptor append bookkeeping Mounting a crafted UDF image with repeated partition descriptors can trigger a heap out-of-bounds write in part_descs_loc[]. handle_partition_descriptor() deduplicates entries by partition number, but appended slots never record partnum. As a result duplicate Partition Descriptors are appended repeatedly and num_part_descs keeps growing. Once the table is full, the growth path still sizes the allocation from partnum even though inserts are indexed by num_part_descs. If partnum is already aligned to PART_DESC_ALLOC_STEP, ALIGN(partnum, step) can keep the old capacity and the next append writes past the end of the table. Store partnum in the appended slot and size growth from the next append count so deduplication and capacity tracking follow the same model.
- CVSS 3.1
- 7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 0.17% probability · 6th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-787
- Affected
- linux/linux kernel
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/058b451b1039f056d1362c4fec2229e522366ab0Patch
- https://git.kernel.org/stable/c/08841b06fa64d8edbd1a21ca6e613420c90cc4b8Patch
- https://git.kernel.org/stable/c/08fa5d818e5bf53c7ca234d88ba334f32004e9b6Patch
- https://git.kernel.org/stable/c/68013a9bd4c01acd42073715f00e1a1992f089ee
- https://git.kernel.org/stable/c/ad3c0c4400686f6f37b382aaa48fac2b9aefccbe
- https://git.kernel.org/stable/c/b5597bb83fc37b5b5da74a4453fa920b932cf39aPatch
- https://git.kernel.org/stable/c/e8474cfbac9ada2cdaa4eaedec22aadfa0f58559
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.