CVE-2026-62958: libriscv: Out of bounds read vuln in the ELF parser (Denial of service)

libriscv is a RISC-V sandbox and emulator. Prior to 1.18, a crafted ELF binary can cause out-of-bounds reads in the host emulator. Memory<W>::binaryloader checks PTLOAD program-header bounds, but Memory<W>::serializeexecutesegment trusts section-header shoffset and shsize when locating .text without verifying the file range against mbinary.size(); Memory<W>::lookup() has a similar section-table problem. Malformed .text or .symtab offsets can therefore bypass the program-header checks and point outside the binary buffer, crashing rvlinux. With suitable memory layout or integer overflow, out-of-buffer host heap memory may instead be mapped into the guest by createexecutesegment(), potentially exposing host memory. The reported reproducer demonstrates a host SIGSEGV, while memory disclosure through grooming is described as possible rather than demonstrated. This issue is fixed in version 1.18.