CVE-2026-10819
Low
No strong exploitation signal.
CVSS base
6.5
MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS — probability of exploitation (30 days)
0.2%
15.4th percentile
CISA KEV
Not listed
Weakness / dates
CWE-409
Published 2026-07-27 · modified 2026-08-03
CVSS breakdown
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
| Attack Vector | N | Network |
| Attack Complexity | L | Low |
| Privileges Required | L | Low |
| User Interaction | N | None |
| Scope | U | Unchanged |
| Confidentiality | N | None |
| Integrity | N | None |
| Availability | H | High |
Timeline
- 2026-07-27 — Published (NVD)
- 2026-08-03 — Last modified (NVD)
Description
Mattermost versions 11.6.x <= 11.6.5, 10.11.x <= 10.11.20, 11.8.x <= 11.8.1, 11.7.x <= 11.7.4 fail to limit the number of frames and enforce the file size cap on animated GIF uploads, which allows an authenticated attacker to cause a denial of service via a crafted animated GIF uploaded as a custom emoji.. Mattermost Advisory ID: MMSA-2026-00695