CVE-2026-18313 rpcapd memory leak in libpcap before 1.10.7
A malicious client can cause rpcapd to leak memory rapidly, leading to denial of service in applications using libpcap.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-18313?
CVE-2026-18313 is a medium-severity denial of service vulnerability in The Tcpdump Group libpcap, published on 5 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
rpcapd can allocate up to 65536 bytes per each RPCAP_MSG_UPDATEFILTER_REQ or RPCAP_MSG_STARTCAP_REQ message received from the client, but it never frees the memory, so it leaks memory even under normal use. A malicious client can cause the server to leak memory substantially faster.
Weakness: CWE-401
Which versions are affected by CVE-2026-18313?
How do I fix CVE-2026-18313?
Upgrade to a fixed version.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-18313 being exploited?
There is no known exploitation of CVE-2026-18313 in the wild and no public exploit code.
Sources
Also known as AZL-99735, DEBIAN-CVE-2026-18313, ECHO-0f8b-361a-a003, GHSA-f2rh-ff9r-fh4j, UBUNTU-CVE-2026-18313.