CVE•Published 2026-05-15•Modified 2026-05-18•0 articles on news•5 live references•NVD data

CVE-2026-4053Mattermost · Mattermost_server

Vulnerability data via NVD (ingested)

CVSS v3.1

3.1

LOW

CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N

EPSS percentile

—

Weaknesses (CWE)

CWE-672Operation on a Resource after Expiration or Release

Description

Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13 fail to enforce the PostEditTimeLimit on non-message post fields which allows an authenticated user to modify post file attachments, props, and pin status after the edit window has expired via the post patch and update API endpoints.. Mattermost Advisory ID: MMSA-2026-00631

Timeline

Published 2026-05-15

Modified 2026-05-18

External references

NVD MITRE Exploit-DB Sploitus VulnCheck

Search for exposed instances

Shodan + Censys queries derived from NVD's CPE data. The vuln tag catches assets Shodan has explicitly linked to this CVE; the product / banner fingerprints find exposed instances even when the vuln tag was never applied (which is common).

Shodan · vuln tag0 hosts

vuln:CVE-2026-4053

Hosts Shodan has explicitly fingerprinted as vulnerable.

Shodan · product

product:"Mattermost Mattermost Server"

All exposed Mattermost Mattermost Server instances — cross-reference with the CVE's affected-version range.

Shodan · banner/body mention

http.html:"Mattermost Server"

HTTP body or banner mentions "Mattermost Server" — catches deploys Shodan didn't identify as a product.

More intel sources (5)

Shodan report

vuln:CVE-2026-4053