CVE-2026-86104
CVE-2026-86104 — Fireware OS Resource Exhaustion in Login Process Allows Denial of Service
An uncontrolled resource consumption vulnerability in the Fireware OS login process (wgagent) allows a remote, unauthenticated attacker to cause a denial of service by sending a specially crafted request.
Published Updated Sources: cvelistV5, WatchGuard
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the scoring sources call it.
Exploitation
Unreported
no source claims exploitation
EPSS
0%
chance of exploitation in 30 days
CVSS base
8.7
HIGH
CISA SSVC assessment
Three decision points CISA publishes for the CVEs it assesses · SSVC 2.0.3. A stakeholder decision, not a severity score.
Exploitation
None
none · proof-of-concept · active
Automatable
Yes
can an attacker script all four kill-chain steps
Technical impact
Partial
partial · total control of the vulnerable component
Affected scope
The catalog records vendors and products as separate lists, not pairs, so which product belongs to which vendor is not something this page can say.
Vendors (1)
Products (1)
Every base score collected
Sources score independently and disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Source |
|---|---|---|---|---|---|
| 8.7 | CVSS 4.0 | HIGH | — | — | cvelistV5 |
Weakness & attack patterns
- CWE-400
- CWE-409
- CWE-770
Attack patterns reported against this CVE. The ATT&CK techniques below are inferred from its weakness class.
- T1499Endpoint Denial of Service
- T1498.001Network Denial of Service: Direct Network Flood
- T1499.003Endpoint Denial of Service: Application Exhaustion Flood
References
1 on the record
- psirt.watchguard.com/CVE-2026-86104
vendor-advisory
Elsewhere on this site
- watchguardevery CVE for this vendor
- CWE-400other pages naming this weakness
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.