CVE-2026-8247

WatchGuard Firebox admd Out of Bounds Write Vulnerability

HIGH

8.8

CVSS Score

Published: July 2, 2026 at 11:07 PM UTC

Updated: October 25, 2026 at 09:10 PM UTC

1 product affected across 1 vendorFireware· also runs on 38 platforms

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Severity

HIGH8.8

Exploit prediction

EPSS 0.4%

SSVC

No known exploit

Description

An Out-of-bounds Write vulnerability in WatchGuard Fireware OS may allow an unauthenticated attacker on the same local network segment to execute arbitrary code. This vulnerability affects Fireware OS 11.0 up to and including 11.12.4_Update1, 12.0 up to and including 12.12 and 2025.1 up to and including 2026.2.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Fireware · WatchGuard

95%

11.0.0 ≤ v < 11.12.412.0 ≤ v < 12.12.112.5 ≤ v < 12.5.192025.1 ≤ v < 2026.2.111.0 11.12.4 11.12.4 u1 12.0 2025.1

Affected range stops below 11.12.4, so it looks safe — our inference, not a vendor statement

Affected range stops below 12.11.9, so it looks safe — our inference, not a vendor statement

Affected range stops below 12.12.1, so it looks safe — our inference, not a vendor statement

Affected range stops below 12.5.19, so it looks safe — our inference, not a vendor statement

Affected range stops below 2026.2.1, so it looks safe — our inference, not a vendor statement

watchguard-firebox-cloud (environment) · watchguard-firebox-m270 (environment) · watchguard-firebox-m290 (environment) · watchguard-firebox-m295 (environment) · watchguard-firebox-m370 (environment) · watchguard-firebox-m390 (environment) · watchguard-firebox-m395 (environment) · watchguard-firebox-m440 (environment) · watchguard-firebox-m4600 (environment) · watchguard-firebox-m470 (environment) · watchguard-firebox-m4800 (environment) · watchguard-firebox-m495 (environment) · watchguard-firebox-m5600 (environment) · watchguard-firebox-m570 (environment) · watchguard-firebox-m5800 (environment) · watchguard-firebox-m590 (environment) · watchguard-firebox-m595 (environment) · watchguard-firebox-m670 (environment) · watchguard-firebox-m690 (environment) · watchguard-firebox-m695 (environment) · watchguard-firebox-nv5 (environment) · watchguard-firebox-t115-w (environment) · watchguard-firebox-t125 (environment) · watchguard-firebox-t125-w (environment) · watchguard-firebox-t145 (environment) · watchguard-firebox-t145-w (environment) · watchguard-firebox-t15 (environment) · watchguard-firebox-t185 (environment) · watchguard-firebox-t20 (environment) · watchguard-firebox-t25 (environment) · watchguard-firebox-t35 (environment) · watchguard-firebox-t40 (environment) · watchguard-firebox-t45 (environment) · watchguard-firebox-t55 (environment) · watchguard-firebox-t70 (environment) · watchguard-firebox-t80 (environment) · watchguard-firebox-t85 (environment) · watchguard-fireboxv (environment)