Buffer Overflow Vulnerability in Fireware OS's SIP Proxy by WatchGuard
CVE-2026-93857

9.2CRITICAL

Key Information:

Vendor

Watchguard

Status
Fireware Os
Vendor
CVE Published:
27 October 2026

Badges

👾 Exploit Exists

What is CVE-2026-93857?

A stack-based buffer overflow vulnerability exists in the SIP proxy of Fireware OS, provided by WatchGuard. This flaw can be exploited by remote, unauthenticated attackers who send specially crafted requests through a policy utilizing the SIP proxy. If successfully triggered, it could lead to arbitrary code execution, potentially compromising system integrity and exposing sensitive data.

Affected Version(s)

Fireware OS Default 2025.1 < 2026.4

Fireware OS Default 12.0 < 12.12.4

Fireware OS T15/T35 12.0 < 12.5.22

References

https://psirt.watchguard.com/CVE-2026-93857
vendor-advisory

CVSS V4

Score:
9.2
Severity:
CRITICAL
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
Physical
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

Credit

Laurent GAFFIE , secorizon.com
.