CVE Explorer
CVE-2026-6340
Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 fail to validate 7zip archive structure before processing which allows an authenticated attacker to cause server memory exhaustion and denial of service via uploading a specially crafted 7zip file with excessive folder declarations.. Mattermost Advisory ID: MMSA-2026-00573
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":"11.5.1","status":"affected","version":"11.5.0","versionType":"semver"},{"lessThanOrEqual":"10.11.13","status":"affected","version":"10.11.0","versionType":"semver"},{"lessThanOrEqual":"11.4.3","status":"affected","version":"11.4.0","versionType":"semver"},{"status":"unaffected","version":"11.6.0"},{"status":"unaffected","version":"11.5.2"},{"status":"unaffected","version":"10.11.14"},{"status":"unaffected","version":"11.4.4"}]}
- cve_program_cvelist_v5affectedurn:baitaphish:normalized-source-record:v2:f9cc6274551ae646d21b6360bf74f5f4e4a5bc8cabe5fab0b1fe19e365203678 · sha256:4cefcd00a00fac84… · /containers/cna/affected/0
Provider-owned CVSS observations
1 source assertion{"metric":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"LOW","baseScore":4.3,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"LOW","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L","version":"3.1"},"metric_type":"cvssV3_1"}
- cve_program_cvelist_v5cvssurn:baitaphish:normalized-source-record:v2:f9cc6274551ae646d21b6360bf74f5f4e4a5bc8cabe5fab0b1fe19e365203678 · sha256:4cefcd00a00fac84… · /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:f9cc6274551ae646d21b6360bf74f5f4e4a5bc8cabe5fab0b1fe19e365203678 · sha256:4cefcd00a00fac84… · /containers/cna/problemTypes/0/descriptions/0
Source references
1 source assertion{"name":"MMSA-2026-00573","tags":["vendor-advisory"],"url":"https://mattermost.com/security-updates"}
- cve_program_cvelist_v5referenceurn:baitaphish:normalized-source-record:v2:f9cc6274551ae646d21b6360bf74f5f4e4a5bc8cabe5fab0b1fe19e365203678 · sha256:4cefcd00a00fac84… · /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.