CVE-2026-81879

radare2 is a UNIX-like reverse engineering framework and command-line toolset. Prior to 6.2.0, radare2's ELF PN_XNUM handling was vulnerable because the ELF parser allocated the program-header array using the resolved PN_XNUM count but several consumers still iterated with the original e_phnum value of 65535. The vulnerability is triggered by processing a crafted ELF file with e_phnum = 0xffff and a much smaller resolved count in shdr[0].sh_info. Consumers iterated beyond the allocated program-header array. This can cause a heap out-of-bounds read and process termination, resulting in denial of service; memory disclosure and code execution have not been demonstrated. This issue is fixed in version 6.2.0.

  • Published Sep 22, 2026
  • CVSS 6.1 medium
  • 0.2% chance of exploitation in the next 30 days (EPSS)
  • Public exploit code is available
  • A fix is available

Affected software

CVE-2026-81879 at the National Vulnerability Database