8.8

CVE-2026-8247: WatchGuard Firebox admd Out of Bounds Write Vulnerability

Analyzed
Published 02-07-2026Last modified 27-08-2026

Vulnerability summary

CVE-2026-8247 is a high (CVSS 8.8) Classic Buffer Overflow vulnerability in watchguard fireware. EPSS estimates a 0.38% chance of exploitation in the next 30 days, higher than 31.1% of scored vulnerabilities.

Overall risk
35/100
0100
Medium · default modelHow is this calculated?
CVSS score
8.8/10
010
High · v3.1 (NVD)
EPSS score
0.38%
0%100%
Low · +0.11 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Timeline

  1. 02-07-2026
    PublishedVulnerability first disclosed.
  2. 27-08-2026
    Last modifiedVulnerability information updated.

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.

CVSS metrics

3 scores · 2 sources · 2 versions

EPSS trend

Probability

0.38%

Chance of exploitation in the next 30 days

Percentile

31%

Versus all other CVEs

30-day change

Increase +0.11 pp

From 0.27% on 22-09-2026

22-09-202622-10-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Watchguard2 products
  • fireware≥ 11.0.0, < 11.12.4 | 11.12.4 | 11.12.4:u1 | ≥ 12.5, < 12.5.19 | ≥ 2025.1, < 2026.2.1 | ≥ 12.0, < 12.12.1
  • fireware os≥ 2025.1, < 2026.2.1 | ≥ 12.0, < 12.12.1 | ≥ 11.0 (No fix recorded) | ≥ 12.0, < 12.11.9 | ≥ 12.0, < 12.5.19

1 vendor · 2 products

References

2 links