Patch Forecast
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CVE-2026-16251

Mattermost versions 11.10.x <= 11.10.0, 11.7.x <= 11.7.9, 11.9.x <= 11.9.1, 11.8.x <= 11.8.5 fail…

Risk score
43/100
CVSS
6.5 v3.1
Exploit chance (30 days)
0.3%
Published
16 Oct 2026

Open in the live forecast Today's forecast

What to know

What it is
Mattermost versions 11.10.x <= 11.10.0, 11.7.x <= 11.7.9, 11.9.x <= 11.9.1, 11.8.x <= 11.8.5 fail to limit the size of remote image responses buffered in memory during local image proxy direct fetches, which allows a remote attacker to cause memory exhaustion on the server via a crafted oversized image response.. Matt…
Affected
See advisory
Fix
Apply the vendor's security update; see the linked advisory.
Exploitation
No known exploitation

Why it is Yellow

  • CVSS 6.5 medium

References

Original description

Mattermost versions 11.10.x <= 11.10.0, 11.7.x <= 11.7.9, 11.9.x <= 11.9.1, 11.8.x <= 11.8.5 fail to limit the size of remote image responses buffered in memory during local image proxy direct fetches, which allows a remote attacker to cause memory exhaustion on the server via a crafted oversized image response.. Mattermost Advisory ID: MMSA-2026-00726

Last activity 16 Oct 2026. Patch Forecast updates every hour.