Description
In the Linux kernel, the following vulnerability has been resolved: s390/bpf: Replace ly instruction with llgf cpu_nr is a 32 bit value and BPF_REG_0 is a 64 bit register, when ly loads the cpu_nr into BPF_REG_0 it does not zero the upper bits, but llgf does.
References2
Metrics
- CVSS 3.1
-
7.8
HIGH
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 6 · as of 8 November 2026
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A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.