CVE-2026-18313Network attack vector

Authenticated service interruption via unreleased filter buffers

Published Sep 5, 2026 · Updated Sep 8, 2026

Memory leak in rpcapd in The Tcpdump Group libpcap 1.9.x and 1.10.x before 1.10.7 allows remote authenticated users to exhaust server memory. daemon_unpackapplyfilter() allocates up to 65,536 bytes for BPF instructions in each UPDATEFILTER or STARTCAP request but never releases the temporary buffer. The remote-capture code is disabled in default builds; exposure requires an enabled rpcapd service and a client connection that reaches message processing, where repetition progressively depletes memory and interrupts service.

CVSS severity4.3
Medium
EPSS probability0.21%
Next 30 days · Sep 17, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Memory leak in rpcapd in The Tcpdump Group libpcap 1.9.x and 1.10.x before 1.10.7 allows remote authenticated users to exhaust server memory. daemon_unpackapplyfilter() allocates up to 65,536 bytes for BPF instructions in each UPDATEFILTER or STARTCAP request but never releases the temporary buffer. The remote-capture code is disabled in default builds; exposure requires an enabled rpcapd service and a client connection that reaches message processing, where repetition progressively depletes memory and interrupts service.

The record

CVE
CVE-2026-18313
Published
Sep 5, 2026
Updated
Sep 8, 2026
Vendor
The Tcpdump Group
Product
libpcap
Classifications
CWE-401, T1499.003
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 5, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 8, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=1.10.x <1.10.7
  2. Affected versionversion=1.9.x

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

The Tcpdump Group · libpcapversion=1.10.x <1.10.7; version=1.9.x

Published CVSS scores

4.3The Tcpdump Group CNACVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 11, 2026Sep 17, 2026
Latest reporting daySep 17, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-401Missing Release of Memory after Effective Lifetime
T1499.003Application Exhaustion Flood

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo