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01 Record

CVE-2026-81665

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

HighPUBLISHEDCNA: redhat
CNA base score7.5 CVSS v3.xCVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
View raw JSON

02 Description

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

03 Exploitation and scoring

Exploitation
Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.
SSVC decision
  • ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
  • AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
  • Technical ImpacttotalSuccessful exploitation gives total control of the vulnerable component.
CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.
EPSS probability
0.41% probability of exploitation activity in the next 30 days.
EPSS percentile
Equal to or higher than the score of 35.5% of scored records. A rank, not a probability.
NVD base score
7.5 (CVSS v3.x), scored by the NVD independently of the CNA.
NVD CVSS vector
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD analysis status
Awaiting Analysis. NVD last modified this record on 2026-10-21.
Red Hat severity
Important. Red Hat's rating for its own products, not a CVSS rating.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

04 Metadata

Published
2026-09-04 09:05Z1 MO AGO
Last updated
2026-10-21 20:43Z7 DAYS AGO
Reserved
2026-08-27
Assigning CNA
redhat
Record state
PUBLISHED
Severity
High (CVSS 7.5)
CNA CVSS vector
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Weaknesses
  • CWE-122Heap-based Buffer OverflowVariant
Data version
5.2
Document digest
48bd6182113f6736a53ffc35cb7d0339c0b13df1c7268a7e6af362f9299f061c

05 Affected products

VendorProductVersionsPlatforms
Red HatRed Hat Enterprise Linux 10Not specified—
Red HatRed Hat Enterprise Linux 10.0 Extended Update SupportNot specified—
Red HatRed Hat Enterprise Linux 7 Extended Lifecycle SupportNot specified—
Red HatRed Hat Enterprise Linux 8Not specified—
Red HatRed Hat Enterprise Linux 8.4 Advanced Mission Critical Update SupportNot specified—
Red HatRed Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-OnNot specified—
Red HatRed Hat Enterprise Linux 8.6 Advanced Mission Critical Update SupportNot specified—
Red HatRed Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-OnNot specified—
Red HatRed Hat Enterprise Linux 8.8 Telecommunications Update ServiceNot specified—
Red HatRed Hat Enterprise Linux 8.8 Update Services for SAP SolutionsNot specified—
Red HatRed Hat Enterprise Linux 9Not specified—
Red HatRed Hat Enterprise Linux 9.2 Update Services for SAP SolutionsNot specified—
Red HatRed Hat Enterprise Linux 9.4 Update Services for SAP SolutionsNot specified—
Red HatRed Hat Enterprise Linux 9.6 Extended Update SupportNot specified—
Red HatRed Hat OpenShift Container Platform 4Not specified—

06 References

07 Fixed in

AlmaLinux 8

  • corosync
    Fixed in 3.1.8-1.el8_10.2
  • corosync-vqsim
    Fixed in 3.1.8-1.el8_10.2
  • corosynclib
    Fixed in 3.1.8-1.el8_10.2
  • corosynclib-devel
    Fixed in 3.1.8-1.el8_10.2
  • spausedd
    Fixed in 3.1.8-1.el8_10.2

Source: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.

AlmaLinux 9

  • corosync
    Fixed in 3.1.10-1.el9_8.2
  • corosync-vqsim
    Fixed in 3.1.10-1.el9_8.2
  • corosynclib
    Fixed in 3.1.10-1.el9_8.2
  • corosynclib-devel
    Fixed in 3.1.10-1.el9_8.2

Source: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.

AlmaLinux 10

  • corosync
    Fixed in 3.1.10-1.el10_2.2
  • corosync-vqsim
    Fixed in 3.1.10-1.el10_2.2
  • corosynclib
    Fixed in 3.1.10-1.el10_2.2
  • corosynclib-devel
    Fixed in 3.1.10-1.el10_2.2

Source: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.

CloudLinux 8

  • corosync
    Fixed in 3.1.8-1.el8_10.2
  • corosync-vqsim
    Fixed in 3.1.8-1.el8_10.2
  • corosynclib
    Fixed in 3.1.8-1.el8_10.2
  • corosynclib-devel
    Fixed in 3.1.8-1.el8_10.2
  • spausedd
    Fixed in 3.1.8-1.el8_10.2

Derived from AlmaLinux 8. Partial coverage: only packages taken from AlmaLinux 8 are listed.

Source: CloudLinux errata, CloudLinux Inc. Derived from: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.

CloudLinux 9

  • corosync
    Fixed in 3.1.10-1.el9_8.2
  • corosync-vqsim
    Fixed in 3.1.10-1.el9_8.2
  • corosynclib
    Fixed in 3.1.10-1.el9_8.2
  • corosynclib-devel
    Fixed in 3.1.10-1.el9_8.2

Derived from AlmaLinux 9. Partial coverage: only packages taken from AlmaLinux 9 are listed.

Source: CloudLinux errata, CloudLinux Inc. Derived from: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.

CloudLinux 10

  • corosync
    Fixed in 3.1.10-1.el10_2.2
  • corosync-vqsim
    Fixed in 3.1.10-1.el10_2.2
  • corosynclib
    Fixed in 3.1.10-1.el10_2.2
  • corosynclib-devel
    Fixed in 3.1.10-1.el10_2.2

Derived from AlmaLinux 10. Partial coverage: only packages taken from AlmaLinux 10 are listed.

Source: CloudLinux errata, CloudLinux Inc. Derived from: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.

Debian 12

  • corosync
    No fix yet

Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.

Debian 13

  • corosync
    No fix yet

Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.

Debian 14

  • corosync
    No fix yet

Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu 16.04 LTS

  • corosync
    No fix yet

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu 18.04 LTS

  • corosync
    No fix yet

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu 20.04 LTS

  • corosync
    No fix yet

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu 22.04 LTS

  • corosync
    No fix yet

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu 24.04 LTS

  • corosync
    No fix yet

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu 26.04 LTS

  • corosync
    No fix yet

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu 26.10

  • corosync
    No fix yet

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

A release or ecosystem missing from this list has no record here. It may be unaffected or not covered by the source. Source notices and licences.