CVE-2022-49450

Vulnérabilité moyenne dans Linux (Linux)

CVSS 5.5 · Moyenne
EPSS 0.3%
Linux•Linux•Versions : <=5.17.*, 5.15.46, 0, <4a3a78b7918bdd723d8c7c9786522ca969bffcc4, 5.19, <61fb38cfbb1d54d3dafd0c25752f684b3cd00b32, <=4.9.*, <88e22159750b0d55793302eeed8ee603f5c1a95c, 5.18.3, <91b34bf0409f43bb60453bab23c5beadd726d022, <=5.10.*, <=4.14.*, 5.10.121, 00e907127e6f86d0f9b122d9b4347a8aa09a8b61, <616f76498d5ddf26b997caf64a95cda3c8a55533, 4.19.247, 5.17.14, 5.4.198, <=5.18.*, <5b4826657d36c218e9f08e8d3223b0edce3de88f, <=5.4.*, <e198f1930050e3115c80b67d9249f80f98a27c67, <4.9, 4.14.283, <=4.19.*, <=*, <b3a9b227d5e7467b8518160ff034ea22bb9de573, 4.9, <=5.15.*, <369de57492c4f1a42563c5a3bd365822ca3bfc79, 4.9.318

Description

In the Linux kernel, the following vulnerability has been resolved: rxrpc: Fix listen() setting the bar too high for the prealloc rings AF_RXRPC's listen() handler lets you set the backlog up to 32 (if you bump up the sysctl), but whilst the preallocation circular buffers have 32 slots in them, one of them has to be a dead slot because we're using CIRC_CNT(). This means that listen(rxrpc_sock, 32) will cause an oops when the socket is closed because rxrpc_service_prealloc_one() allocated one too many calls and rxrpc_discard_prealloc() won't then be able to get rid of them because it'll think the ring is empty. rxrpc_release_calls_on_socket() then tries to abort them, but oopses because call->peer isn't yet set. Fix this by setting the maximum backlog to RXRPC_BACKLOG_MAX - 1 to match the ring capacity. BUG: kernel NULL pointer dereference, address: 0000000000000086 ... RIP: 0010:rxrpc_send_abort_packet+0x73/0x240 [rxrpc] Call Trace: <TASK> ? __wake_up_common_lock+0x7a/0x90 ? rxrpc_notify_socket+0x8e/0x140 [rxrpc] ? rxrpc_abort_call+0x4c/0x60 [rxrpc] rxrpc_release_calls_on_socket+0x107/0x1a0 [rxrpc] rxrpc_release+0xc9/0x1c0 [rxrpc] __sock_release+0x37/0xa0 sock_close+0x11/0x20 __fput+0x89/0x240 task_work_run+0x59/0x90 do_exit+0x319/0xaa0

Gravité et risque d'exploitation

CVE-2022-49450 obtient un score CVSS de 5.5/10, soit une gravité moyenne. Selon le modèle EPSS, la probabilité qu'elle soit exploitée dans les 30 prochains jours est de 0.29 %, ce qui la place devant 20.3 % des CVE référencées.

Que faire ?

  • Vérifiez si Linux (versions <=5.17.*, 5.15.46, 0, <4a3a78b7918bdd723d8c7c9786522ca969bffcc4, 5.19, <61fb38cfbb1d54d3dafd0c25752f684b3cd00b32, <=4.9.*, <88e22159750b0d55793302eeed8ee603f5c1a95c, 5.18.3, <91b34bf0409f43bb60453bab23c5beadd726d022, <=5.10.*, <=4.14.*, 5.10.121, 00e907127e6f86d0f9b122d9b4347a8aa09a8b61, <616f76498d5ddf26b997caf64a95cda3c8a55533, 4.19.247, 5.17.14, 5.4.198, <=5.18.*, <5b4826657d36c218e9f08e8d3223b0edce3de88f, <=5.4.*, <e198f1930050e3115c80b67d9249f80f98a27c67, <4.9, 4.14.283, <=4.19.*, <=*, <b3a9b227d5e7467b8518160ff034ea22bb9de573, 4.9, <=5.15.*, <369de57492c4f1a42563c5a3bd365822ca3bfc79, 4.9.318) 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