Monitor vulnerabilities like this one.
Sign up free to get alerted when software you use is affected.
9.1
CVE-2026-56015: Perl's Net::IP::LPM versions through 1.10 allow data to be read past its limits
CVE-2026-56015
CVE-2026-56015
Summary
A bug in the Net::IP::LPM module for Perl could allow an attacker to access memory they shouldn't. This bug is not likely to cause direct harm but could be detected by certain security tools. To stay safe, update to a version of Net::IP::LPM that is newer than 1.10.
What to do
No fix is available yet. Check with your software vendor for updates.
Affected software
| Vendor | Product | Affected versions |
|---|---|---|
| tpoder | net::ip::lpm | <= 1.10 |
Original title
Net::IP::LPM versions through 1.10 for Perl allow a heap out-of-bounds read via an unbounded prefix length
Original description
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.
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.
Vulnerability type
CWE-125
Out-of-bounds Read
Published: 3 Jul 2026 · Updated: 23 Jul 2026 · First seen: 3 Jul 2026