https://seclists.org/oss-sec/2026/q4/305: one moason to update libpcap to at least 1.10.7

Q: Which deployments are exposed to the newly identified attack path?

Deployments using a vulnerable libpcap version are exposed when they compile a filter expression containing the "protochain" primitive. Support for this primitive is conditional but enabled by default, making this path applicable to common configurations.

Q: What must an attacker control to trigger the issue?

An attacker needs a crafted packet to be processed by the filter program generated from a filter expression using "protochain." The packet may come from a network or from a file.

Q: What is the operational effect of successful exploitation?

The resulting filter program can enter an infinite loop while processing the crafted packet. This can cause the affected processing to stop making progress.

Q: What remediation is identified?

Update libpcap to at least version 1.10.7. The same fix addresses both the previously known and newly identified attack vectors.

Published Oct 22, 2026

Updated

Affected Software

1 affected component

libpcap libpcap<1.10.7

Frequently Asked Questions

Which deployments are exposed to the newly identified attack path?

Deployments using a vulnerable libpcap version are exposed when they compile a filter expression containing the "protochain" primitive. Support for this primitive is conditional but enabled by default, making this path applicable to common configurations.

What must an attacker control to trigger the issue?

An attacker needs a crafted packet to be processed by the filter program generated from a filter expression using "protochain." The packet may come from a network or from a file.

What is the operational effect of successful exploitation?

The resulting filter program can enter an infinite loop while processing the crafted packet. This can cause the affected processing to stop making progress.

What remediation is identified?

Update libpcap to at least version 1.10.7. The same fix addresses both the previously known and newly identified attack vectors.