What’s Vulnerable › Vulnerabilities

CVE-2024-41096: PCI/MSI: Fix UAF in msi_capability_init

• Severity: high (CVSS 7.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2024-07-29 · updated 2026-08-04
• Weakness: CWE-416

Description

In the Linux kernel, the following vulnerability has been resolved: PCI/MSI: Fix UAF in msi_capability_init KFENCE reports the following UAF: BUG: KFENCE: use-after-free read in __pci_enable_msi_range+0x2c0/0x488 Use-after-free read at 0x0000000024629571 (in kfence-#12): __pci_enable_msi_range+0x2c0/0x488 pci_alloc_irq_vectors_affinity+0xec/0x14c pci_alloc_irq_vectors+0x18/0x28 kfence-#12: 0x0000000008614900-0x00000000e06c228d, size=104, cache=kmalloc-128 allocated by task 81 on cpu 7 at 10.808142s: __kmem_cache_alloc_node+0x1f0/0x2bc kmalloc_trace+0x44/0x138 msi_alloc_desc+0x3c/0x9c msi_domain_insert_msi_desc+0x30/0x78 msi_setup_msi_desc+0x13c/0x184 __pci_enable_msi_range+0x258/0x488 pci_alloc_irq_vectors_affinity+0xec/0x14c pci_alloc_irq_vectors+0x18/0x28 freed by task 81 on cpu 7 at 10.811436s: msi_domain_free_descs+0xd4/0x10c msi_domain_free_locked.part.0+0xc0/0x1d8 msi_domain_alloc_irqs_all_locked+0xb4/0xbc pci_msi_setup_msi_irqs+0x30/0x4c __pci_enable_msi_range+0x2a8/0x488 pci_alloc_irq_vectors_affinity+0xec/0x14c pci_alloc_irq_vectors+0x18/0x28 Descriptor allocation done in: __pci_enable_msi_range msi_capability_init msi_setup_msi_desc msi_insert_msi_desc msi_domain_insert_msi_desc msi_alloc_desc ... Freed in case of failure in __msi_domain_alloc_locked() __pci_enable_msi_range msi_capability_init pci_msi_setup_msi_irqs msi_domain_alloc_irqs_all_locked msi_domain_alloc_locked __msi_domain_alloc_locked => fails msi_domain_free_locked ... That failure propagates back to pci_msi_setup_msi_irqs() in msi_capability_init() which accesses the descriptor for unmasking in the error exit path. Cure it by copying the descriptor and using the copy for the error exit path unmask operation. [ tglx: Massaged change log ]

Affected products

• Debian Linux: 11.0
• Linux kernel: from 5.17 before 6.1.109; from 6.2 before 6.6.37; from 6.7 before 6.9.8 — fixed in 6.1.109, 6.6.37, 6.9.8

How to fix

Upgrade to a fixed version: Linux kernel 6.1.109, 6.6.37, 6.9.8. Check the vendor advisory for mitigations.

References

• https://git.kernel.org/stable/c/0ae40b2d0a5de6b045504098e365d4fdff5bbeba
• https://git.kernel.org/stable/c/45fc8d20e0768ab0a0ad054081d0f68aa3c83976
• https://git.kernel.org/stable/c/9eee5330656bf92f51cb1f09b2dc9f8cf975b3d1
• https://git.kernel.org/stable/c/ff1121d2214b794dc1772081f27bdd90721a84bc
• https://git.kernel.org/stable/c/45fc8d20e0768ab0a0ad054081d0f68aa3c83976
• https://git.kernel.org/stable/c/9eee5330656bf92f51cb1f09b2dc9f8cf975b3d1
• https://git.kernel.org/stable/c/ff1121d2214b794dc1772081f27bdd90721a84bc
• https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html

Get alerted when CVE-2024-41096 or the next vulnerability affects your stack