CVE-2026-35092 | Corosync: corosync: denial of service via integer overflow in join message validation

Exp

A flaw was found in Corosync. An integer overflow vulnerability in Corosync's join message sanity validation allows a remote, unauthenticated attacker to send crafted User Datagram Protocol (UDP) packets. This can cause the service to crash, leading to a denial of service. This vulnerability specifically affects Corosync deployments configured to use totemudp/totemudpu mode.

Published: 2026-04-01 Last update: 2026-05-26 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-35092 is rated High Exploit Risk (65.6/100): CVSS High severity, with medium exploitation likelihood (EPSS 0.36%). Core evidence: 1 public exploit reference(s) are indexed (Exploit-DB). Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2026-35092

EDB-ID Source Kind Published Link
nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2026-35092

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-27 0.27% 0.36% +0.09%
2 2026-05-13 0.21% 0.27% +0.07%
3 2026-04-21 0.21%

Full EPSS history (5 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-35092

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
3.9 3.6 [email protected]

Weakness enumeration for CVE-2026-35092

GitHub Security Advisory for CVE-2026-35092

GHSA-g4g9-h6f9-v5x2 · Severity: high — A flaw was found in Corosync. An integer overflow vulnerability in Corosync's join message sanity...

OS Trackers for CVE-2026-35092

vendor priority summary link
debian not yet assigned CVE-2026-35092 not yet assigned priority: Debian including 1 source packages (corosync), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2026-35092
redhat medium https://access.redhat.com/security/cve/CVE-2026-35092
suse high CVE-2026-35092 severity important: SUSE including 24 source package names (corosync, corosync-2.4.6-150300.12.16.1, …), 79 product×package rows across 9 product lines (SUSE Linux Enterprise High Availability Extension 12 SP5, SUSE Linux Enterprise High Availability Extension 15 SP4, … (9 product lines)): Fixed 73, Known Not Affected 6. https://www.suse.com/security/cve/CVE-2026-35092/
ubuntu medium CVE-2026-35092 medium priority: Ubuntu including 1 source packages (corosync), 7 status rows across 7 suites (bionic, focal, jammy, noble, questing, upstream, xenial): needs-triage 4, released 3. https://ubuntu.com/security/CVE-2026-35092

Affected software / configurations for CVE-2026-35092

Vendor Product Version Raw CPE
corosync corosync cpe:2.3:a:corosync:corosync:-:*:*:*:*:*:*:*
redhat openshift 4.0 cpe:2.3:a:redhat:openshift:4.0:*:*:*:*:*:*:*
redhat enterprise_linux 7.0 cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*
redhat enterprise_linux 8.0 cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*
redhat enterprise_linux 9.0 cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:*
redhat enterprise_linux 10.0 cpe:2.3:o:redhat:enterprise_linux:10.0:*:*:*:*:*:*:*

References for CVE-2026-35092

URL Tags
https://access.redhat.com/errata/RHSA-2026:13644
https://access.redhat.com/errata/RHSA-2026:13657
https://access.redhat.com/errata/RHSA-2026:13673
https://access.redhat.com/errata/RHSA-2026:14205
https://access.redhat.com/errata/RHSA-2026:14210
https://access.redhat.com/errata/RHSA-2026:14211
https://access.redhat.com/errata/RHSA-2026:14212
https://access.redhat.com/errata/RHSA-2026:14213
https://access.redhat.com/errata/RHSA-2026:14214
https://access.redhat.com/errata/RHSA-2026:14215
https://access.redhat.com/errata/RHSA-2026:14216
https://access.redhat.com/errata/RHSA-2026:19043
https://access.redhat.com/errata/RHSA-2026:19200
https://access.redhat.com/errata/RHSA-2026:20916
https://access.redhat.com/security/cve/CVE-2026-35092 Third Party Advisory VDB Entry
https://bugzilla.redhat.com/show_bug.cgi?id=2453169 Exploit Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2453814 Issue Tracking Third Party Advisory
cvelogic Threat Intelligence