CVE-2026-90082 net: mana: Cap MSI-X vectors to the device MSI-X table size
A missing bounds check in the Linux kernel's mana network driver allows a local attacker to trigger a page fault and system crash by exhausting MSI-X vectors.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-90082?
CVE-2026-90082 is a denial of service vulnerability in Linux, published on 17 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
net: mana: Cap MSI-X vectors to the device MSI-X table size
mana_gd_query_max_resources() sizes gc->num_msix_usable from resp.max_msix and the CPU count, but never from the device MSI-X table. On a 1792 vCPU M-series VM that yields 1793 while the table has 1024 entries, and mana_gd_setup_remaining_irqs() then walks indices 1..1792, running off the end of the region mapped by msix_map_region():
BUG: unable to handle page fault for address: ff8e347f8b99800c RIP: 0010:msix_prepare_msi_desc+0x7a/0x90 RAX: 0000000000004000 RBX: ff4330cb164ea780 RCX: ff8e347f8b998000 Call Trace: <TASK> __msi_domain_alloc_irqs+0x13a/0x440 msi_domain_alloc_irq_at+0x149/0x1b0 mana_gd_setup+0x351/0x890 mana_gd_probe+0x274/0x390 </TASK>
RAX is index 1024 * PCI_MSIX_ENTRY_SIZE, one entry past the table.
msi_insert_desc() does range check the index, but only against the MSI domain hwsize, which matches the table only for devices on an MSI parent domain. With a global PCI/MSI domain hwsize is MSI_XA_DOMAIN_SIZE, so nothing bounds the request.
Cap num_msix_usable with pci_msix_vec_count().
Which versions are affected by CVE-2026-90082?
How do I fix CVE-2026-90082?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-90082 being exploited?
There is no known exploitation of CVE-2026-90082 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-90082, DEBIAN-CVE-2026-90082, GHSA-34r8-cjx6-5m3m, UBUNTU-CVE-2026-90082.