Vulnerability in The Tcpdump Group Libpcap
CVE-2026-18313
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.
CVSS v3 metric
CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L.
Affected products
- The Tcpdump Group Libpcap — versions 1.9.x
Weakness classification (CWE)
References
- security@tcpdump.org (patch)
Frequently asked questions
- What is CVE-2026-18313?
- CVE-2026-18313 is a medium-severity vulnerability in The Tcpdump Group Libpcap, classified under Missing Release of Memory after Effective Lifetime. CVSS score: 4.3/10. Published 2026-09-05.
- How severe is CVE-2026-18313?
- Medium severity. CVSS v3 base score is 4.3 out of 10.