Description

In the Linux kernel, the following vulnerability has been resolved:

crypto: ccp - Fix null pointer dereference in __sev_snp_shutdown_locked

Fix a null pointer dereference induced by DEBUG_TEST_DRIVER_REMOVE.
Return from __sev_snp_shutdown_locked() if the psp_device or the
sev_device structs are not initialized. Without the fix, the driver will
produce the following splat:

ccp 0000:55:00.5: enabling device (0000 -> 0002)
ccp 0000:55:00.5: sev enabled
ccp 0000:55:00.5: psp enabled
BUG: kernel NULL pointer dereference, address: 00000000000000f0
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC NOPTI
CPU: 262 PID: 1 Comm: swapper/0 Not tainted 6.9.0-rc1+ #29
RIP: 0010:__sev_snp_shutdown_locked+0x2e/0x150
Code: 00 55 48 89 e5 41 57 41 56 41 54 53 48 83 ec 10 41 89 f7 49 89 fe 65 48 8b 04 25 28 00 00 00 48 89 45 d8 48 8b 05 6a 5a 7f 06 <4c> 8b a0 f0 00 00 00 41 0f b6 9c 24 a2 00 00 00 48 83 fb 02 0f 83
RSP: 0018:ffffb2ea4014b7b8 EFLAGS: 00010286
RAX: 0000000000000000 RBX: ffff9e4acd2e0a28 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffb2ea4014b808
RBP: ffffb2ea4014b7e8 R08: 0000000000000106 R09: 000000000003d9c0
R10: 0000000000000001 R11: ffffffffa39ff070 R12: ffff9e49d40590c8
R13: 0000000000000000 R14: ffffb2ea4014b808 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff9e58b1e00000(0000) knlGS:0000...

Classification

CVE ID: CVE-2024-43874

CVSS Base Severity: MEDIUM

CVSS Base Score: 5.5

CVSS Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected Products

Vendor: Linux

Product: Linux

Exploit Prediction Scoring System (EPSS)

EPSS Score: 0.04% (probability of being exploited)

EPSS Percentile: 13.22% (scored less or equal to compared to others)

EPSS Date: 2025-06-02 (when was this score calculated)

Stakeholder-Specific Vulnerability Categorization (SSVC)

SSVC Exploitation: none

SSVC Technical Impact: partial

SSVC Automatable: false

References

https://nvd.nist.gov/vuln/detail/CVE-2024-43874
https://git.kernel.org/stable/c/bbf2c94503f6a421ed9b79e300d8085810da765d
https://git.kernel.org/stable/c/468e3295774d0edce15f4ae475913b5076dd4f40

Timeline