CVE-2026-35091 (GCVE-0-2026-35091)

Vulnerability from cvelistv5 – Published: 2026-04-01 13:18 – Updated: 2026-05-05 10:22
VLAI?
Title
Corosync: corosync: denial of service and information disclosure via crafted udp packet
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. This vulnerability affects Corosync when running in totemudp/totemudpu mode, which is the default configuration.
Severity ?
8.2 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H
CWE
  • CWE-253 - Incorrect Check of Function Return Value
Assigner
References
Impacted products
Vendor Product Version
Red Hat Red Hat Enterprise Linux 10 Unaffected: 0:3.1.9-2.el10_1.1 , < * (rpm)
    cpe:/o:redhat:enterprise_linux:10.1
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    Red Hat Red Hat Enterprise Linux 8 Unaffected: 0:3.1.8-1.el8_10.1 , < * (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
 Create a notification for this product.
    Red Hat Red Hat Enterprise Linux 7     cpe:/o:redhat:enterprise_linux:7
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    Red Hat Red Hat Enterprise Linux 9     cpe:/o:redhat:enterprise_linux:9
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    Red Hat Red Hat OpenShift Container Platform 4     cpe:/a:redhat:openshift:4
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Date Public ?
2026-04-01 11:48
Credits
Red Hat would like to thank Sebastián Alba Vives for reporting this issue.
Show details on NVD website
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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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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.
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  • 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.



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