CVE Explorer
CVE-2026-2456
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
Known exploited
Not asserted
Disputed
No
Stale source
No
Conflicts
0
Affected products and versions
1 source assertion{"defaultStatus":"unaffected","product":"Mattermost","vendor":"Mattermost","versions":[{"lessThanOrEqual":"11.3.0","status":"affected","version":"11.3.0","versionType":"semver"},{"lessThanOrEqual":"11.2.2","status":"affected","version":"11.2.0","versionType":"semver"},{"lessThanOrEqual":"10.11.10","status":"affected","version":"10.11.0","versionType":"semver"},{"status":"unaffected","version":"11.4.0"},{"status":"unaffected","version":"11.3.1"},{"status":"unaffected","version":"11.2.3"},{"status":"unaffected","version":"10.11.11"}]}
- cve_program_cvelist_v5affectedurn:baitaphish:normalized-source-record:v2:01c56fb5be128a1f648b2ecf3905afd1473d9608dcf5bb4eae71ec0d9dd6ead0 · sha256:4e3b05a05fd28939… · /containers/cna/affected/0
Provider-owned CVSS observations
1 source assertion{"metric":{"attackComplexity":"HIGH","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":5.3,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"REQUIRED","vectorString":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:H","version":"3.1"},"metric_type":"cvssV3_1"}
- cve_program_cvelist_v5cvssurn:baitaphish:normalized-source-record:v2:01c56fb5be128a1f648b2ecf3905afd1473d9608dcf5bb4eae71ec0d9dd6ead0 · sha256:4e3b05a05fd28939… · /containers/cna/metrics/0/cvssV3_1
CWE assertions
1 source assertion{"cweId":"CWE-789","description":"CWE-789: Memory Allocation with Excessive Size Value","lang":"en","type":"CWE"}
- cve_program_cvelist_v5cweurn:baitaphish:normalized-source-record:v2:01c56fb5be128a1f648b2ecf3905afd1473d9608dcf5bb4eae71ec0d9dd6ead0 · sha256:4e3b05a05fd28939… · /containers/cna/problemTypes/0/descriptions/0
Source references
1 source assertion{"name":"MMSA-2026-00571","tags":["vendor-advisory"],"url":"https://mattermost.com/security-updates"}
- cve_program_cvelist_v5referenceurn:baitaphish:normalized-source-record:v2:01c56fb5be128a1f648b2ecf3905afd1473d9608dcf5bb4eae71ec0d9dd6ead0 · sha256:4e3b05a05fd28939… · /containers/cna/references/0
Attribution and limitations
- CVE Program CVEList V5: Reproduce the MITRE copyright designation and CVE license in copies. Source →
Provider severity values are preserved separately. Baitaphish does not convert them into a risk rating, infer affected products, or treat EPSS as observed exploitation.