CVE-2026-89763
Açıklama (NVD)
In the Linux kernel, the following vulnerability has been resolved: KEYS: trusted: Fix TPM teardown ordering trusted_tpm_exit() drops the TPM chip reference and frees the digest array before unregistering the trusted key type. key_type_lookup() holds key_types_sem for reading until the key operation finishes, while unregister_key_type() takes it for writing. It therefore provides the synchronization point that must precede backend teardown. The current order permits this interleaving: CPU 0 CPU 1 trusted_tpm_exit() key_type_lookup("trusted") put_device(&chip->dev) trusted_tpm_seal() kfree(digests) pcrlock() unregister_key_type() tpm_pcr_extend(..., digests) CPU 1 can consequently dereference the freed digest array. The chip can also be released before callbacks stop using it. KASAN reported: BUG: KASAN: slab-use-after-free in tpm_pcr_extend+0x1f0/0x200 Read of size 2 at addr ffff88810872d000 by task poc/89 Call Trace: tpm_pcr_extend+0x1f0/0x200 pcrlock+0x42/0x70 [trusted] trusted_tpm_seal+0x1b6/0x570 [trusted] trusted_instantiate+0x293/0x340 [trusted] __key_instantiate_and_link+0xb2/0x2b0 __key_create_or_update+0x61e/0xb50 __do_sys_add_key+0x1b8/0x310 Allocated by task 88: __kmalloc_noprof+0x1a7/0x490 do_one_initcall+0xa1/0x390 do_init_module+0x2df/0x840 Freed by task 90: kfree+0x131/0x3c0 trusted_tpm_exit+0x59/0xa0 [trusted] __do_sys_delete_module+0x346/0x510 Move unregister_key_type() before releasing either resource. This stops new lookups and waits for in-flight key operations to finish before the backend state is destroyed.
Yayın: 11.09.2026 · Son değişiklik: 30.10.2026
CVSS 3.1 metrikleri
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
| Saldırı vektörü | Yerel |
| Karmaşıklık | Düşük |
| Gereken yetki | Düşük |
| Kullanıcı etkileşimi | Gerekmez |
| Kapsam | Değişmez |
| Gizlilik | Yüksek |
| Bütünlük | Yüksek |
| Erişilebilirlik | Yüksek |
Hesaplanan temel puan: 7.8. CVSS hesaplayıcıda incele
Referanslar
- https://git.kernel.org/stable/c/2f7541afbc57fe9d26769a22c31d8ce8790c9a19
- https://git.kernel.org/stable/c/3d67b4acbfc7af331d887a8efc04bef6573b8a7a
- https://git.kernel.org/stable/c/5e2d672280d97d83de43031d93761b12dadd7b8a
- https://git.kernel.org/stable/c/6564808189c9a1e682ee7b5e70f5f1c73c89c3a4
- https://git.kernel.org/stable/c/753c978f2400f9783eb524842a975d3ac950d511
- https://git.kernel.org/stable/c/81dfc6c665547a4e41721b6716f894f263a5e03f
- https://git.kernel.org/stable/c/b254cdadbcb6bdd0daf7391d63b3b97b2bec1ad9
- https://git.kernel.org/stable/c/c96518231608bbf9568f539aadb20a8e366b54c7