Mattermost versions 11.4.x <= 11.4.0, 11.3.x <= 11.3.1, 11.2.x <= 11.2.3, 10.11.x <= 10.11.11 fail to validate decompressed archive entry sizes during file extraction which allows authenticated users with file upload permissions to cause a denial of service via crafted zip archives containing highly compressed entries (zip bombs) that exhaust server memory.. Mattermost Advisory ID: MMSA-2026-00598
CVE-2026-3114
This medium-severity CVE scores 6.5 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.3%, top 73% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).
- Lower severity and no public exploit yet
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 6.5
- EG Score
- 6.5(medium)
- EG Risk
- 34(Track)EG Risk 34/100SSVC: Track
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity65% × 45%Exploitation0% × 40%Automatability30% × 15%Action: Routine — remediate on your standard cadence. - EPSS PROB
- 0%
- EPSS %ILE
- 28%
- KEV
- Not listed
Published
March 26, 2026
Last Modified
June 17, 2026
Advisory Details (1)
Auto-updated Aug 3, 2026Affected Packages
(4 across 1 ecosystem)
Go(4)
| Package | Vulnerable range | Fixed in | Dependents |
|---|---|---|---|
| github.com/mattermost/mattermost-server | — | 11.4.1+incompatible | — |
| github.com/mattermost/mattermost-server/v5 | — | — | — |
| github.com/mattermost/mattermost-server/v6 | — | — | — |
| github.com/mattermost/mattermost/server/v8 | 11.4.0 | 8.0.0-20260217110922-b7d4a1f1f59b | — |
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 8× in last 7d / 28× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-09-18 19:28 UTCEPSS rescore
- 2026-09-18 19:28 UTCEPSS rescore
- 2026-09-17 19:30 UTCEPSS rescore
- 2026-09-16 14:08 UTCEPSS rescore
- 2026-09-16 05:15 UTCEPSS rescore
- 2026-09-15 03:11 UTCEPSS rescore
- 2026-09-13 16:47 UTCEPSS rescore
- 2026-09-12 15:01 UTCEPSS rescore
- 2026-09-11 14:53 UTCEPSS rescore
- 2026-09-11 09:37 UTCEPSS rescore
- 2026-09-10 09:34 UTCEPSS rescore
- 2026-09-08 22:00 UTCEPSS rescore
- 2026-09-07 16:01 UTCEPSS rescore
- 2026-09-06 13:47 UTCEPSS rescore
- 2026-09-04 05:06 UTCEPSS rescore
- 2026-09-02 14:12 UTCEPSS rescore
- 2026-09-02 13:26 UTCOSV refresh
- 2026-09-01 13:53 UTCEPSS rescore
- 2026-09-01 04:39 UTCEPSS rescore
- 2026-08-30 19:17 UTCEPSS rescore
- 2026-08-30 01:22 UTCEPSS rescore
- 2026-08-28 21:41 UTCEPSS rescore
- 2026-08-27 14:25 UTCEPSS rescore
- 2026-08-26 14:46 UTCEPSS rescore
- 2026-08-25 13:49 UTCEPSS rescore
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- 2026-08-23 00:19 UTCEPSS rescore
- 2026-08-21 23:49 UTCEPSS rescore
- 2026-08-20 22:55 UTCEPSS rescore
- 2026-08-19 17:03 UTCEPSS rescore
- 2026-08-18 13:48 UTCEPSS rescore
- 2026-08-17 13:47 UTCEPSS rescore
- 2026-08-16 14:56 UTCEPSS rescore
- 2026-08-16 10:07 UTCEG score recompute
- 2026-08-16 02:14 UTCEPSS rescore
- 2026-08-15 01:30 UTCEPSS rescore
- 2026-08-14 06:25 UTCEG score recompute
- 2026-08-13 22:00 UTCEPSS rescore
- 2026-08-12 23:12 UTCEG score recompute
- 2026-08-12 13:51 UTCEPSS rescore
- 2026-08-11 20:49 UTCEG score recompute
- 2026-08-11 13:43 UTCEPSS rescore
- 2026-08-11 00:00 UTCEPSS rescore
- 2026-08-10 08:22 UTCEG score recompute
- 2026-08-09 13:46 UTCEPSS rescore
- 2026-08-09 05:58 UTCEG score recompute
- 2026-08-08 16:37 UTCEPSS rescore
- 2026-08-07 16:24 UTCEG score recompute
- 2026-08-06 13:46 UTCEPSS rescore
- 2026-08-06 00:52 UTCEG score recompute
- 2026-08-05 19:17 UTCEPSS rescore
- 2026-08-04 15:10 UTCEPSS rescore
- 2026-08-04 10:38 UTCEPSS rescore
- 2026-08-03 23:17 UTCEG score recompute
- 2026-08-03 10:36 UTCEPSS rescore
- 2026-08-02 15:22 UTCEG score recompute
- 2026-08-02 02:27 UTCEPSS rescore
- 2026-08-01 04:16 UTCEPSS rescore
- 2026-07-30 16:28 UTCEPSS rescore
- 2026-07-30 01:30 UTCEPSS rescore
- 2026-07-27 14:21 UTCEG score recompute
Frequently asked(5)
What is CVE-2026-3114?
When was CVE-2026-3114 disclosed?
Is CVE-2026-3114 actively exploited?
What is the CVSS score of CVE-2026-3114?
How do I remediate CVE-2026-3114?
Dependency Blast Radius
See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-3114
Is Your Infrastructure Affected by CVE-2026-3114?
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