CVE-2026-56015
CriticalCVSS 9.1Exploitation Probability (EPSS)
Low risk41th percentile - higher than 41% of all known CVEs
Summary
In the Net::IP::LPM library for Perl versions up to 1.10, a heap out-of-bounds read vulnerability was found. The add() function does not validate the prefix length against the address width, allowing an overly long prefix (e.g., /255 for IPv4 or IPv6). This causes a read beyond the packed address buffer during trie construction.
Risk Assessment
An attacker can cause a process crash (e.g., via AddressSanitizer or hardened allocator) by supplying a crafted address with an excessive prefix length. Although the read data is not exposed through the module's API, the vulnerability can lead to application denial of service.
Recommendation
Update the Net::IP::LPM library to a version newer than 1.10, which includes prefix length validation. If an update is unavailable, restrict trusted input sources passed to the add() function.
Original NVD description (English source)
Net::IP::LPM versions through 1.10 for Perl allow a heap out-of-bounds read via an unbounded prefix length. add() passes the prefix string to the trie builder addPrefixToTrie() without checking it against the address width. addPrefixToTrie() then walks the prefix buffer by prefix_length bits, reading prefix[byte] for byte up to prefix_len/8, where prefix is the 4-byte (IPv4) or 16-byte (IPv6) packed address. A prefix length greater than 32 for IPv4 or 128 for IPv6, for example add("1.2.3.4/255", $v) or add("2001:db8::/255", $v), reads past the end of the packed address. The out-of-bounds read happens during trie construction and is bounded: the prefix length is stored as an unsigned char, so the bit walk reads at most 32 bytes from the start of the packed address, a short distance past the end of the 4-byte or 16-byte buffer. It is detectable under AddressSanitizer, valgrind, or a hardened allocator, where it can abort the process. Lookups and dump() format only the valid address width, so the out-of-bounds bytes are not exposed through the module's API.