CVE-2026-95520: Out-of-bounds Write

A heap-based buffer overflow flaw was found in rpm. Parsing a symlink entry in an untrusted RPM package whose declared RPMTAG_LONGFILESIZES value is 0xFFFFFFFFFFFFFFFF causes an integer overflow in iterReadArchiveNext() that shrinks a buffer allocation to one byte, after which the payload's independently-controlled cpio filesize field is used to write attacker-controlled data past the end of that allocation. This is reachable via rpm2cpio, rpm2archive, and rpm -qlvp on an untrusted package.