CVE-2026-93857

Fireware OS Pre-Authentication Stack Buffer Overflow in SIP Proxy Allows Remote Code Execution

CRITICAL

9.2

CVSS Score

Published: October 27, 2026 at 03:52 PM UTC

Updated: October 29, 2026 at 11:17 AM UTC

1 product affected across 1 vendorFireware

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Severity

CRITICAL9.2

Exploit prediction

EPSS 0.5%

SSVC

No known exploit

Description

A stack-based buffer overflow vulnerability in Fireware OS's SIP proxy allows a remote, unauthenticated attacker to execute arbitrary code by sending a specially crafted request through a policy that uses the SIP proxy.

Affected

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

Fireware · WatchGuard

90%

12.0 2025.1

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references

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

References (1)

Vendor Advisory

Source: cverecord

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

SSVC — Action Prioritization

SSVCNo known exploitAutomatableTotal impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

9.2CRITICALWatchGuard

Vector?

Quick Info

StatusAWAITING ANALYSIS

CWE

CWE-120CWE-121CWE-787

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