CVE-2026-48682 Memory corruption in n/a
An out-of-bounds read in FastNetMon's IPv4 parser allows attackers to cause denial of service or disclose memory via crafted packets.
- 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-2026-48682?
CVE-2026-48682 is a medium-severity memory corruption vulnerability in n/a, published on 2 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
FastNetMon Community Edition through 1.2.9 contains an out-of-bounds read in the IPv4 packet parser. In src/simple_packet_parser_ng.cpp, after validating that the packet contains at least sizeof(ipv4_header_t) bytes (20 bytes), the code advances the local_pointer by '4 * ipv4_header->get_ihl()' (line 164) without validating that (a) IHL >= 5 (the minimum valid value per RFC 791), or (b) 4 * IHL bytes are actually available in the packet. The IHL field is 4 bits, allowing values 0-15, so the advance can be 0-60 bytes. An IHL value of 15 with only 20 bytes validated causes a 40-byte over-read. An IHL of 0-4 causes the pointer to not advance past the IP header, resulting in the TCP/UDP header being parsed from IP header data (type confusion). This vulnerability is reachable via any packet capture interface.
Weakness: CWE-125
Which versions are affected by CVE-2026-48682?
How do I fix CVE-2026-48682?
No fix has been published for CVE-2026-48682 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-2026-48682 being exploited?
There is no known exploitation of CVE-2026-48682 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-48682, GHSA-p5cp-vqjq-6cj7, UBUNTU-CVE-2026-48682.