CVE-2026-35091

Summary

A flaw was found in Corosync. A remote unauthenticated attacker can exploit a wrong return value vulnerability in the Corosync membership commit token sanity check by sending a specially crafted User Datagram Protocol (UDP) packet. This can lead to an out-of-bounds read, causing a denial of service (DoS) and potentially disclosing limited memory contents

Affected Software

VendorProductVersion RangeStatus
Red HatRed Hat Enterprise Linux 100:3.1.9-2.el10_1.1 < *unaffected
Red HatRed Hat Enterprise Linux 100:3.1.10-1.el10_2.1 < *unaffected
Red HatRed Hat Enterprise Linux 10.0 Extended Update Support0:3.1.9-1.el10_0.2 < *unaffected
Red HatRed Hat Enterprise Linux 7 Extended Lifecycle Support0:2.4.5-7.el7_9.3 < *unaffected
Red HatRed Hat Enterprise Linux 80:3.1.8-1.el8_10.1 < *unaffected
Red HatRed Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support0:3.1.0-3.el8_4.2 < *unaffected
Red HatRed Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On0:3.1.0-3.el8_4.2 < *unaffected
Red HatRed Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support0:3.1.5-2.el8_6.1 < *unaffected
Red HatRed Hat Enterprise Linux 8.6 Telecommunications Update Service0:3.1.5-2.el8_6.1 < *unaffected
Red HatRed Hat Enterprise Linux 8.6 Update Services for SAP Solutions0:3.1.5-2.el8_6.1 < *unaffected
Red HatRed Hat Enterprise Linux 8.8 Telecommunications Update Service0:3.1.7-1.el8_8.1 < *unaffected
Red HatRed Hat Enterprise Linux 8.8 Update Services for SAP Solutions0:3.1.7-1.el8_8.1 < *unaffected
Red HatRed Hat Enterprise Linux 90:3.1.9-2.el9_7.1 < *unaffected
Red HatRed Hat Enterprise Linux 90:3.1.10-1.el9_8.1 < *unaffected
Red HatRed Hat Enterprise Linux 9.0 Update Services for SAP Solutions0:3.1.5-3.el9_0.1 < *unaffected
Red HatRed Hat Enterprise Linux 9.2 Update Services for SAP Solutions0:3.1.7-1.el9_2.1 < *unaffected
Red HatRed Hat Enterprise Linux 9.4 Extended Update Support0:3.1.8-1.el9_4.1 < *unaffected
Red HatRed Hat Enterprise Linux 9.6 Extended Update Support0:3.1.9-2.el9_6.1 < *unaffected

Weaknesses

  • CWE-253: Incorrect Check of Function Return Value

Workarounds

Systems using totemudp or totemudpu should migrate to the supported knet transport and enable encryption.

Disabling the Corosync service is a valid workaround if clustering is not required, but for active clusters, enabling encryption via knet is the preferred and recommended approach.

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: yes
    • Technical Impact: partial

References