Vulnerability in Linux

CVE-2024-43840

In the Linux kernel, the following vulnerability has been resolved: bpf, arm64: Fix trampoline for BPF_TRAMP_F_CALL_ORIG When BPF_TRAMP_F_CALL_ORIG is set, the trampoline calls __bpf_tramp_enter() and __bpf_tramp_exit() functions, passing them the struct bpf_tramp_image *im pointer as an argument in R0. The trampoline generation code uses emit_addr_mov_i64() to emit instructions for moving the bpf_tramp_image address into R0, but emit_addr_mov_i64() assumes the address to be in the vmalloc() space and uses only 48 bits. Because bpf_tramp_image is allocated using kzalloc(), its address can use more than 48-bits, in this case the trampoline will pass an invalid address to __bpf_tramp_enter/exit() causing a kernel crash. Fix this by using emit_a64_mov_i64() in place of emit_addr_mov_i64() as it can work with addresses that are greater than 48-bits.

EPSS: 0.002 (12.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Affected products

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2024-43840?
CVE-2024-43840 is a high-severity vulnerability in Linux. CVSS score: 7.8/10. Published 2024-08-17.
How severe is CVE-2024-43840?
High severity. CVSS v3 base score is 7.8 out of 10.
Is CVE-2024-43840 known to be exploited?
2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.