Vulnerability-Lookup

OPENSUSE-SU-2026:21887-1

Vulnerability from csaf_opensuse - Published: 2026-09-20 04:53 - Updated: 2026-09-24 17:48

Summary

Security update for corosync

Severity

Important

Notes

Title of the patch: Security update for corosync

Description of the patch: This update for corosync fixes the following issues: - CVE-2026-81665: heap-based buffer overflow in totempg assembly buffer during fragmented message reassembly (bsc#1278738). - CVE-2026-81666: integer overflow in check_memb_commit_token_sanity may bypass message length validation on 32-bit systems (bsc#1278739).

Patchnames: openSUSE-Leap-16.0-1714

CVE-2026-81665

7.5 (High)


                
                  CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

Recommended 12 products

Product	Version	Remediation
Unresolved product id: openSUSE Leap 16.0:corosync-0:3.1.9-160000.4.1.aarch64	—	Vendor Fix
Unresolved product id: openSUSE Leap 16.0:corosync-0:3.1.9-160000.4.1.ppc64le	—	Vendor Fix
Unresolved product id: openSUSE Leap 16.0:corosync-0:3.1.9-160000.4.1.s390x	—	Vendor Fix
Unresolved product id: openSUSE Leap 16.0:corosync-0:3.1.9-160000.4.1.x86_64	—	Vendor Fix
Unresolved product id: openSUSE Leap 16.0:corosync-devel-0:3.1.9-160000.4.1.aarch64	—	Vendor Fix
Unresolved product id: openSUSE Leap 16.0:corosync-devel-0:3.1.9-160000.4.1.ppc64le	—	Vendor Fix
Unresolved product id: openSUSE Leap 16.0:corosync-devel-0:3.1.9-160000.4.1.s390x	—	Vendor Fix
Unresolved product id: openSUSE Leap 16.0:corosync-devel-0:3.1.9-160000.4.1.x86_64	—	Vendor Fix
Unresolved product id: openSUSE Leap 16.0:corosync-libs-0:3.1.9-160000.4.1.aarch64	—	Vendor Fix
Unresolved product id: openSUSE Leap 16.0:corosync-libs-0:3.1.9-160000.4.1.ppc64le	—	Vendor Fix
Unresolved product id: openSUSE Leap 16.0:corosync-libs-0:3.1.9-160000.4.1.s390x	—	Vendor Fix
Unresolved product id: openSUSE Leap 16.0:corosync-libs-0:3.1.9-160000.4.1.x86_64	—	Vendor Fix

Threats

Impact important

CVE-2026-81666

6.5 (Medium)


                
                  CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

Recommended 12 products, the same list as for CVE-2026-81665

Threats

Impact moderate

References

10 references

URL	Category
https://www.suse.com/support/security/rating/	external
https://ftp.suse.com/pub/projects/security/csaf/o…	self
https://bugzilla.suse.com/1278738	self
https://bugzilla.suse.com/1278739	self
https://www.suse.com/security/cve/CVE-2026-81665/	self
https://www.suse.com/security/cve/CVE-2026-81666/	self
https://www.suse.com/security/cve/CVE-2026-81665	external
https://bugzilla.suse.com/1278738	external
https://www.suse.com/security/cve/CVE-2026-81666	external
https://bugzilla.suse.com/1278739	external

JSON

To clipboard

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  "vulnerabilities": [
    {
      "cve": "CVE-2026-81665",
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          "text": "https://www.suse.com/security/cve/CVE-2026-81665"
        }
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      "notes": [
        {
          "category": "general",
          "text": "A heap-based buffer overflow was found in Corosync\u0027s 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.",
          "title": "CVE description"
        }
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CVE-2026-81665 (GCVE-0-2026-81665)

Vulnerability from cvelistv5 – Published: 2026-09-04 09:05 – Updated: 2026-09-21 16:12

Title

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

Summary

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.

Severity

7.5 (High)


                        
                          CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

SSVC

Exploitation: none Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-04 17:09 UTC

CWE

CWE-122 - Heap-based Buffer Overflow

Assigner

redhat redhat root

References

13 references

URL	Tags
https://access.redhat.com/errata/RHSA-2026:67872	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:67873	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:67878	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:67879	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:67880	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:67881	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:68574	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:69277	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:69278	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:69279	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:69280	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/security/cve/CVE-2026-81665	vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2524910	issue-trackingx_refsource_REDHAT

Impacted products

15 products

Vendor	Product	Version
Red Hat	Red Hat Enterprise Linux 10	Unaffected: 0:3.1.10-1.el10_2.2 , < * (rpm) cpe:/o:redhat:enterprise_linux:10.2
Red Hat	Red Hat Enterprise Linux 10.0 Extended Update Support	Unaffected: 0:3.1.9-1.el10_0.3 , < * (rpm) cpe:/o:redhat:enterprise_linux_eus:10.0
Red Hat	Red Hat Enterprise Linux 7 Extended Lifecycle Support	Unaffected: 0:2.4.5-7.el7_9.4 , < * (rpm) cpe:/o:redhat:enterprise_linux:7::server
Red Hat	Red Hat Enterprise Linux 8	Unaffected: 0:3.1.8-1.el8_10.2 , < * (rpm) cpe:/a:redhat:enterprise_linux:8::appstream cpe:/a:redhat:enterprise_linux:8::crb cpe:/a:redhat:enterprise_linux:8::highavailability cpe:/a:redhat:enterprise_linux:8::resilientstorage
Red Hat	Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support	Unaffected: 0:3.1.0-3.el8_4.3 , < * (rpm) cpe:/a:redhat:rhel_aus:8.4::appstream cpe:/a:redhat:rhel_aus:8.4::highavailability cpe:/a:redhat:rhel_eus_long_life:8.4::appstream cpe:/a:redhat:rhel_eus_long_life:8.4::highavailability cpe:/a:redhat:rhel_eus_long_life:8.4::resilientstorage
Red Hat	Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On	Unaffected: 0:3.1.0-3.el8_4.3 , < * (rpm) cpe:/a:redhat:rhel_aus:8.4::appstream cpe:/a:redhat:rhel_aus:8.4::highavailability cpe:/a:redhat:rhel_eus_long_life:8.4::appstream cpe:/a:redhat:rhel_eus_long_life:8.4::highavailability cpe:/a:redhat:rhel_eus_long_life:8.4::resilientstorage
Red Hat	Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support	Unaffected: 0:3.1.5-2.el8_6.2 , < * (rpm) cpe:/a:redhat:rhel_aus:8.6::appstream cpe:/a:redhat:rhel_eus_long_life:8.6::appstream cpe:/a:redhat:rhel_eus_long_life:8.6::highavailability cpe:/a:redhat:rhel_eus_long_life:8.6::resilientstorage
Red Hat	Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On	Unaffected: 0:3.1.5-2.el8_6.2 , < * (rpm) cpe:/a:redhat:rhel_aus:8.6::appstream cpe:/a:redhat:rhel_eus_long_life:8.6::appstream cpe:/a:redhat:rhel_eus_long_life:8.6::highavailability cpe:/a:redhat:rhel_eus_long_life:8.6::resilientstorage
Red Hat	Red Hat Enterprise Linux 8.8 Telecommunications Update Service	Unaffected: 0:3.1.7-1.el8_8.2 , < * (rpm) cpe:/a:redhat:rhel_e4s:8.8::appstream cpe:/a:redhat:rhel_e4s:8.8::highavailability cpe:/a:redhat:rhel_tus:8.8::appstream cpe:/a:redhat:rhel_tus:8.8::highavailability
Red Hat	Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions	Unaffected: 0:3.1.7-1.el8_8.2 , < * (rpm) cpe:/a:redhat:rhel_e4s:8.8::appstream cpe:/a:redhat:rhel_e4s:8.8::highavailability cpe:/a:redhat:rhel_tus:8.8::appstream cpe:/a:redhat:rhel_tus:8.8::highavailability
Red Hat	Red Hat Enterprise Linux 9	Unaffected: 0:3.1.10-1.el9_8.2 , < * (rpm) cpe:/a:redhat:enterprise_linux:9::appstream cpe:/a:redhat:enterprise_linux:9::crb cpe:/a:redhat:enterprise_linux:9::highavailability cpe:/a:redhat:enterprise_linux:9::resilientstorage
Red Hat	Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions	Unaffected: 0:3.1.7-1.el9_2.2 , < * (rpm) cpe:/a:redhat:rhel_e4s:9.2::appstream cpe:/a:redhat:rhel_e4s:9.2::highavailability cpe:/a:redhat:rhel_e4s:9.2::resilientstorage
Red Hat	Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions	Unaffected: 0:3.1.8-1.el9_4.2 , < * (rpm) cpe:/a:redhat:rhel_e4s:9.4::appstream cpe:/a:redhat:rhel_e4s:9.4::highavailability cpe:/a:redhat:rhel_e4s:9.4::resilientstorage
Red Hat	Red Hat Enterprise Linux 9.6 Extended Update Support	Unaffected: 0:3.1.9-2.el9_6.2 , < * (rpm) cpe:/a:redhat:rhel_eus:9.6::appstream cpe:/a:redhat:rhel_eus:9.6::crb cpe:/a:redhat:rhel_eus:9.6::highavailability cpe:/a:redhat:rhel_eus:9.6::resilientstorage
Red Hat	Red Hat OpenShift Container Platform 4	cpe:/a:redhat:openshift:4

Date Public

2026-09-04 08:30

Credits

Red Hat would like to thank Tristan Madani (Talence Security) for reporting this issue.

Show details on NVD website

JSON

To clipboard

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CVE-2026-81666 (GCVE-0-2026-81666)

Vulnerability from cvelistv5 – Published: 2026-09-04 09:46 – Updated: 2026-09-08 14:41

Title

Corosync: corosync: integer overflow in check_memb_commit_token_sanity may bypass message length validation on 32-bit systems

Summary

An integer overflow was found in Corosync's handling of membership commit token messages. The length-validation check for these messages can be bypassed on 32-bit systems due to an integer overflow in the calculation of the expected message length, allowing a crafted network packet to trigger an out-of-bounds memory access that crashes the Corosync daemon. This results in a denial of service for the affected cluster node. The overflow does not occur on 64-bit systems, where the length calculation is correctly performed in 64-bit arithmetic.

Severity

6.5 (Medium)


                        
                          CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-08 14:41 UTC

CWE

CWE-190 - Integer Overflow or Wraparound

Assigner

redhat redhat root

References

2 references

URL	Tags
https://access.redhat.com/security/cve/CVE-2026-81666	vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2524923	issue-trackingx_refsource_REDHAT

Impacted products

5 products

Vendor	Product	Version
Red Hat	Red Hat Enterprise Linux 10	cpe:/o:redhat:enterprise_linux:10
Red Hat	Red Hat Enterprise Linux 7	cpe:/o:redhat:enterprise_linux:7
Red Hat	Red Hat Enterprise Linux 8	cpe:/o:redhat:enterprise_linux:8
Red Hat	Red Hat Enterprise Linux 9	cpe:/o:redhat:enterprise_linux:9
Red Hat	Red Hat OpenShift Container Platform 4	cpe:/a:redhat:openshift:4

Date Public

2026-09-04 08:14

Credits

Red Hat would like to thank Tristan Madani (Talence Security) for reporting this issue.

Show details on NVD website

JSON

To clipboard

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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

Action not permitted

OPENSUSE-SU-2026:21887-1

CVE-2026-81665 (GCVE-0-2026-81665)

CVE-2026-81666 (GCVE-0-2026-81666)

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Related by attack behaviour