CVE-2026-56015 Net::IP::LPM versions before 1.11 for Perl allow a heap out-of-bounds read via an unbounded prefix length
A heap out-of-bounds read in Net::IP::LPM allows attackers to cause a denial of service via crafted prefix lengths.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-56015?
CVE-2026-56015 is a critical memory corruption vulnerability, published on 3 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Net::IP::LPM versions before 1.11 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.
Weakness: CWE-125
Which versions are affected by CVE-2026-56015?
How do I fix CVE-2026-56015?
No fix has been published for CVE-2026-56015 yet. Limit exposure of the affected software until one is available.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-56015 being exploited?
There is no known exploitation of CVE-2026-56015 in the wild and no public exploit code.
Sources
Also known as GHSA-q2wj-rfvr-wf9p.