CVE-2026-103593
Fireware OS Stack Buffer Overflow in Logging Service Allows Remote Code Execution
No known exploitation. EPSS puts it in the 1st percentile. Fixed versions are out.
No public exploit knownFix1 product2 fixed builds listed below
No ready-made check. Neither Nuclei nor OpenVAS has one for this CVE yet.
What to do
Find your product and version, then upgrade to the build on the right.
- WatchGuard Fireware OSAffected: ≥ 2025.1, < 2026.4Upgrade to: 2026.4Affected: ≥ 12.0, < 12.12.4Upgrade to: 12.12.4Stated by: CVE record
Versions as the sources state them. Full version matrix after sign-in
What it is
From the CVE record
A stack-based buffer overflow vulnerability in the Fireware OS logging service allows a network-adjacent attacker who can impersonate or intercept traffic to the configured log server to execute arbitrary code with root privileges by presenting a specially crafted certificate.
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
0.1% chance of exploitation activity in the next 30 days, which ranks it in the 1st percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
12 events over 2 days, from the signal feeds we watch.
- Patch availablepatch available, record updated, record updated
- Patch availablerecord updated
- Patch availablepatch available, published, weakness classified, att&ck mapped, record updated
Affected products
Technical detail
Weaknesses
ATT&CK techniques
Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.
- Initial AccessT1190Exploit Public-Facing Applicationhigh confidence
- Privilege EscalationT1068Exploitation for Privilege Escalationhigh confidence
Sources
References in the record
In the news
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