Description
In BPF instructions that load/store a value from/to a scratch memory register the register index is an unsigned 32-bit integer and must not exceed 15, but libpcap BPF interpreter does not validate the value. In particular uncommon use cases a crafted filter program can cause the interpreter to try reading and writing the OS process memory in the 16GiB starting at the current stack frame on 64-bit architectures and in the entire address space on 32-bit architectures.
References1
Metrics
- CVSS 3.1
-
8.7
HIGH
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:L/I:H/A:H - EPSS — exploit probability
- 0% percentile: 1 · as of 3 November 2026
- CWE
- CWE-125CWE-129CWE-787
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