CVE-2022-49788

Description

In the Linux kernel, the following vulnerability has been resolved: misc/vmw_vmci: fix an infoleak in vmci_host_do_receive_datagram() `struct vmci_event_qp` allocated by qp_notify_peer() contains padding, which may carry uninitialized data to the userspace, as observed by KMSAN: BUG: KMSAN: kernel-infoleak in instrument_copy_to_user ./include/linux/instrumented.h:121 instrument_copy_to_user ./include/linux/instrumented.h:121 _copy_to_user+0x5f/0xb0 lib/usercopy.c:33 copy_to_user ./include/linux/uaccess.h:169 vmci_host_do_receive_datagram drivers/misc/vmw_vmci/vmci_host.c:431 vmci_host_unlocked_ioctl+0x33d/0x43d0 drivers/misc/vmw_vmci/vmci_host.c:925 vfs_ioctl fs/ioctl.c:51 ... Uninit was stored to memory at: kmemdup+0x74/0xb0 mm/util.c:131 dg_dispatch_as_host drivers/misc/vmw_vmci/vmci_datagram.c:271 vmci_datagram_dispatch+0x4f8/0xfc0 drivers/misc/vmw_vmci/vmci_datagram.c:339 qp_notify_peer+0x19a/0x290 drivers/misc/vmw_vmci/vmci_queue_pair.c:1479 qp_broker_attach drivers/misc/vmw_vmci/vmci_queue_pair.c:1662 qp_broker_alloc+0x2977/0x2f30 drivers/misc/vmw_vmci/vmci_queue_pair.c:1750 vmci_qp_broker_alloc+0x96/0xd0 drivers/misc/vmw_vmci/vmci_queue_pair.c:1940 vmci_host_do_alloc_queuepair drivers/misc/vmw_vmci/vmci_host.c:488 vmci_host_unlocked_ioctl+0x24fd/0x43d0 drivers/misc/vmw_vmci/vmci_host.c:927 ... Local variable ev created at: qp_notify_peer+0x54/0x290 drivers/misc/vmw_vmci/vmci_queue_pair.c:1456 qp_broker_attach drivers/misc/vmw_vmci/vmci_queue_pair.c:1662 qp_broker_alloc+0x2977/0x2f30 drivers/misc/vmw_vmci/vmci_queue_pair.c:1750 Bytes 28-31 of 48 are uninitialized Memory access of size 48 starts at ffff888035155e00 Data copied to user address 0000000020000100 Use memset() to prevent the infoleaks. Also speculatively fix qp_notify_peer_local(), which may suffer from the same problem.

Gravité et risque d'exploitation

CVE-2022-49788 obtient un score CVSS de 0.0/10, soit une gravité non évaluée. Selon le modèle EPSS, la probabilité qu'elle soit exploitée dans les 30 prochains jours est de 0.23 %, ce qui la place devant 13.4 % des CVE référencées.

Que faire ?

• Vérifiez si Linux (versions 5.4.225, <62634b43d3c4e1bf62fd540196f7081bf0885c0a, <8e2f33c598370bcf828bab4d667d1d38bcd3c57d, <f04586c2315cfd03d72ad0395705435e7ed07b1a, 0, 06164d2b72aa752ce4633184b3e0d97601017135, <3.9, <5a275528025ae4bc7e2232866856dfebf84b2fad, <=4.9.*, <=5.10.*, <=4.14.*, <=6.0.*, <7ccf7229b96fadc3a185d1391f814a604c7ef609, <76c50d77b928a33e5290aaa9fdc10e88254ff8c7, <e5b0d06d9b10f5f43101bd6598b076c347f9295f, <=5.4.*, 4.14.300, <=4.19.*, <e7061dd1fef2dfb6458cd521aef27aa66f510d31, 6.1, 4.19.267, <=*, <=5.15.*, 5.15.80, 5.10.156, 4.9.334, 6.0.10, 3.9) est présent sur votre parc.
• Appliquez le correctif ou la version corrigée indiqués dans les références de l'éditeur.
• À défaut de correctif, limitez l'exposition (filtrage réseau, désactivation du composant).
• Automatisez la détection : les agents CVE Heimdall (gratuits, open source) corrèlent l'inventaire de vos serveurs avec la base CVE.

Références

• https://git.kernel.org/stable/c/7ccf7229b96fadc3a185d1391f814a604c7ef609
• https://git.kernel.org/stable/c/f04586c2315cfd03d72ad0395705435e7ed07b1a
• https://git.kernel.org/stable/c/5a275528025ae4bc7e2232866856dfebf84b2fad
• https://git.kernel.org/stable/c/e7061dd1fef2dfb6458cd521aef27aa66f510d31
• https://git.kernel.org/stable/c/62634b43d3c4e1bf62fd540196f7081bf0885c0a
• https://git.kernel.org/stable/c/8e2f33c598370bcf828bab4d667d1d38bcd3c57d
• https://git.kernel.org/stable/c/76c50d77b928a33e5290aaa9fdc10e88254ff8c7
• https://git.kernel.org/stable/c/e5b0d06d9b10f5f43101bd6598b076c347f9295f