VPN processing interruption via iked integer underflow
Published Aug 27, 2026 · Updated Aug 27, 2026
Integer underflow in WatchGuard Fireware OS allows remote attackers to interrupt IKEv1 VPN processing with crafted network traffic. The iked process performs integer arithmetic that underflows while handling the traffic, leading to an out-of-bounds write and buffer-overflow condition; the affected IKE field is undisclosed. Exploitation requires a configured Branch Office VPN using IKEv1, and the bounded consequence is disruption of VPN processing rather than device compromise.
Summary
What happened
Integer underflow in WatchGuard Fireware OS allows remote attackers to interrupt IKEv1 VPN processing with crafted network traffic. The iked process performs integer arithmetic that underflows while handling the traffic, leading to an out-of-bounds write and buffer-overflow condition; the affected IKE field is undisclosed. Exploitation requires a configured Branch Office VPN using IKEv1, and the bounded consequence is disruption of VPN processing rather than device compromise.
The record
- CVE
- CVE-2026-19314
- Published
- Aug 27, 2026
- Updated
- Aug 27, 2026
- Vendor
- WatchGuard Technologies, Inc.
- Product
- Fireware OS
- Classifications
- CWE-191, CWE-787, CAPEC-100, CAPEC-92, T1499.004
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Aug 27, 2026CVE publishedPublication date reported by the CVE source.
- Aug 27, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=12.0 <12.12.2
- Affected versionversion=12.0 <12.5.20
- Affected versionversion=2025.0 <2026.2.2
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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