Riskcovery

CVE-2026-81665

Corosync: corosync: heap-based buffer overflow in totempg assembly buffer during fragmented message reassembly

State
Published
Severity
7.5 High
Published
Sep 4, 2026
Updated
Oct 21, 2026
Reserved
Aug 27, 2026

Read the record on cve.org

Description

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.

Scores

CVSSScoreVectorSource
3.17.5 HighCVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:Hredhat

Weaknesses

Affected Products

ProductVersions
Red Hat Enterprise Linux 10Red Hat
  • 0:3.1.10-1.el10_2.2 and laterNot affected
Red Hat Enterprise Linux 10.0 Extended Update SupportRed Hat
  • 0:3.1.9-1.el10_0.3 and laterNot affected
Red Hat Enterprise Linux 7 Extended Lifecycle SupportRed Hat
  • 0:2.4.5-7.el7_9.4 and laterNot affected
Red Hat Enterprise Linux 8Red Hat
  • 0:3.1.8-1.el8_10.2 and laterNot affected
Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update SupportRed Hat
  • 0:3.1.0-3.el8_4.3 and laterNot affected
Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-OnRed Hat
  • 0:3.1.0-3.el8_4.3 and laterNot affected
Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update SupportRed Hat
  • 0:3.1.5-2.el8_6.2 and laterNot affected
Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-OnRed Hat
  • 0:3.1.5-2.el8_6.2 and laterNot affected
Red Hat Enterprise Linux 8.8 Telecommunications Update ServiceRed Hat
  • 0:3.1.7-1.el8_8.2 and laterNot affected
Red Hat Enterprise Linux 8.8 Update Services for SAP SolutionsRed Hat
  • 0:3.1.7-1.el8_8.2 and laterNot affected
Red Hat Enterprise Linux 9Red Hat
  • 0:3.1.10-1.el9_8.2 and laterNot affected
Red Hat Enterprise Linux 9.2 Update Services for SAP SolutionsRed Hat
  • 0:3.1.7-1.el9_2.2 and laterNot affected
Red Hat Enterprise Linux 9.4 Update Services for SAP SolutionsRed Hat
  • 0:3.1.8-1.el9_4.2 and laterNot affected
Red Hat Enterprise Linux 9.6 Extended Update SupportRed Hat
  • 0:3.1.9-2.el9_6.2 and laterNot affected
Red Hat OpenShift Container Platform 4Red Hat
    Red Hat OpenShift Container Platform 4Red Hat

      References

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