CVE-2026-81665

CVE CVE-2026-81665EUVD EUVD-2026-70978Published 2026-09-04T09:05:35.000ZLast changed 2026-09-04T18:25:16.000ZCVSS 7.5

What the advisory describes

A heap-based buffer overflow was found in Corosync's Totem Process Group (totempg) message reassembly. When processing fragmented multicast messages, the buffer used to reassemble fragments lacks a runtime bounds check in release builds. A network-adjacent attacker able to send crafted multicast protocol messages to the cluster could cause a heap buffer overflow with attacker-controlled data. This can crash the Corosync daemon, causing a denial of service to the entire cluster, and may potentially allow further exploitation given sufficient heap-corruption control.

Source: EUVD (ENISA), in the words of the advisory.

Products the advisory names

These come from the advisory itself, not from any check we performed.

• Red Hat — Red Hat Enterprise Linux 10
• Red Hat — Red Hat Enterprise Linux 7
• Red Hat — Red Hat Enterprise Linux 8
• Red Hat — Red Hat Enterprise Linux 9
• Red Hat — Red Hat OpenShift Container Platform 4

The versions shown are the advisory's own. Patchlage compares no version numbers and derives no judgement from them — which version is installed is something a person has to look up.

Carried in the product catalogue

An estate covering these products can be recorded in Patchlage. An advisory about them appears in the next morning's situation report.

• Red Hat — Red Hat Enterprise Linux
• Red Hat — Red Hat OpenShift Container Platform

Patchlage reports hits and suspected hits. About everything else this system says nothing — neither this page nor the situation report ever claims that an estate is safe.