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.

Published · last modified .

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.

EPSS exploit prediction

EPSS: 0.002 (12.6th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 13th percentile — 12.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-18313: held from 0.002 to 0.002.

EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: +0.000

Affected products

Weakness classification (CWE)

References

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.