CVE-2026-2456 (GCVE-0-2026-2456)

Vulnerability from cvelistv5 – Published: 2026-03-16 11:06 – Updated: 2026-03-16 13:49
VLAI
Title
Denial of Service via Unbounded Memory Allocation in Integration Actions
Summary
Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 Mattermost fails to limit the size of responses from integration action endpoints, which allows an authenticated attacker to cause server memory exhaustion and denial of service via a malicious integration server that returns an arbitrarily large response when a user clicks an interactive message button.. Mattermost Advisory ID: MMSA-2026-00571
Severity
5.3 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:H
CWE
  • CWE-789 - Memory Allocation with Excessive Size Value
Assigner
References
URL Tags
https://mattermost.com/security-updates vendor-advisory
Impacted products
Vendor Product Version
Mattermost Mattermost Affected: 11.3.0 , ≤ 11.3.0 (semver)
Affected: 11.2.0 , ≤ 11.2.2 (semver)
Affected: 10.11.0 , ≤ 10.11.10 (semver)
Unaffected: 11.4.0
Unaffected: 11.3.1
Unaffected: 11.2.3
Unaffected: 10.11.11
Create a notification for this product.
Credits
Daniel Espino Garcia
Show details on NVD website
To clipboard 

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  • 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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