In the Linux kernel, the following vulnerability has been resolved:
nvme: fix FDP fdpcidx bounds check
The fdpcidx bounds check sets n = NUMFDPC + 1 but used > instead of >=,
incorrectly accepting fdp_idx when it equals n (i.e. NUMFDPC + 1).
CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS Score: 9.8
AV:N - The bug is in the NVMe host driver while parsing Get Features/Get Log responses during namespace scan; a malicious NVMe-oF target can deliver crafted FDP data over TCP/RDMA to any host already using remote NVMe storage, which is the highest-impact reachable deployment.
AC:L - An attacker controlling the NVMe endpoint fully sets fdpcidx and numfdpc in protocol responses and can reliably make fdpcidx equal numfdpc+1, walk one descriptor past the valid list, and hit the out-of-bounds read without races or victim-specific heap layout.
PR:N - Exploitation needs no local account or capabilities on the victim; a remote malicious/compromised NVMe-oF target (or physical device inserted by an attacker) triggers parsing during connect/rescan/AEN-driven namespace scans without further local authorization.
UI:N - No victim user action is required at exploit time because namespace scanning and AEN-triggered rescans run automatically in kernel workqueues once a controller is present, and a remote target can force rescans with Notice Namespace Changed events.
S:U - Impact is confined to kernel memory and block-layer metadata on the host parsing the malicious device responses; it does not cross a VM, container, or IOMMU security boundary into a separate authority.
C:H - Accepting fdpcidx=numfdpc+1 lets the descriptor walk advance past the last valid FDP configuration and then reads desc->nrg and desc->runs out of bounds, leaking adjacent kvmalloc/heap contents or attacker-crafted bytes from beyond the valid descriptor array.
I:H - The out-of-bounds descriptor fields are copied into info->runs and influence queue write_stream_granularity limits, giving attacker-controlled modification of kernel block-layer state from memory corruption primitives that can be chained beyond a simple crash.
A:H - If the out-of-bounds descriptor pointer lies past the allocated FDP log buffer, accessing desc->nrg/desc->runs can fault the kernel (oops/panic); even successful parsing still represents unsafe memory access with high availability risk under attacker control.
| Attack Vector |
Network |
Scope |
Unchanged |
| Attack Complexity |
Low |
Confidentiality Impact |
High |
| Privileges Required |
None |
Integrity Impact |
High |
| User Interaction |
None |
Availability Impact |
High |
AV:N - The bug is in the NVMe host driver while parsing Get Features/Get Log responses during namespace scan; a malicious NVMe-oF target can deliver crafted FDP data over TCP/RDMA to any host already using remote NVMe storage, which is the highest-impact reachable deployment.
AC:L - An attacker controlling the NVMe endpoint fully sets fdpcidx and numfdpc in protocol responses and can reliably make fdpcidx equal numfdpc+1, walk one descriptor past the valid list, and hit the out-of-bounds read without races or victim-specific heap layout.
PR:N - Exploitation needs no local account or capabilities on the victim; a remote malicious/compromised NVMe-oF target (or physical device inserted by an attacker) triggers parsing during connect/rescan/AEN-driven namespace scans without further local authorization.
UI:N - No victim user action is required at exploit time because namespace scanning and AEN-triggered rescans run automatically in kernel workqueues once a controller is present, and a remote target can force rescans with Notice Namespace Changed events.
S:U - Impact is confined to kernel memory and block-layer metadata on the host parsing the malicious device responses; it does not cross a VM, container, or IOMMU security boundary into a separate authority.
C:H - Accepting fdpcidx=numfdpc+1 lets the descriptor walk advance past the last valid FDP configuration and then reads desc->nrg and desc->runs out of bounds, leaking adjacent kvmalloc/heap contents or attacker-crafted bytes from beyond the valid descriptor array.
I:H - The out-of-bounds descriptor fields are copied into info->runs and influence queue write_stream_granularity limits, giving attacker-controlled modification of kernel block-layer state from memory corruption primitives that can be chained beyond a simple crash.
A:H - If the out-of-bounds descriptor pointer lies past the allocated FDP log buffer, accessing desc->nrg/desc->runs can fault the kernel (oops/panic); even successful parsing still represents unsafe memory access with high availability risk under attacker control.
CVSS 3.1