Loading story…
WatchGuard disclosed two high-severity vulnerabilities in Fireware OS affecting Firebox appliances, including a path traversal flaw in the Web UI tracked as CVE-2026-3987 and an insecure deserialization issue in the Access Portal tracked as CVE-2026-4266. The Web UI bug can let a privileged, authenticated remote attacker perform an arbitrary file write and potentially execute code in the context of an elevated system process. The Access Portal flaw can lead to arbitrary code execution as the portald user through insecure deserialization.
The issues affect multiple Fireware OS release lines, with CVE-2026-3987 impacting versions 12.6.1 through 12.11.8 and 2025.1 through 2026.1.2, while CVE-2026-4266 affects versions 12.1 through 12.11.8 and 2025.1 through 2026.1.2. WatchGuard said the deserialization bug is not a standalone remote exploit and requires prior write access to the local filesystem, making it more relevant for post-compromise chaining. The vulnerabilities are mapped to CWE-22 and CWE-502, respectively, and WatchGuard published vendor guidance including advisory WGSA-2026-00009; Firebox models without Access Portal support, such as the T-15 and T-35, are not affected by the Access Portal issue.
Mallory correlates global threat intelligence with your attack surface — know if you’re exposed before adversaries strike.
4 events from the most recent confirmed update back to the earliest known activity.
WatchGuard published advisory WGSA-2026-00025 for a Firebox Access Portal vulnerability involving a hardcoded fallback encryption key in the resource credential database. This is a separate disclosure from the previously tracked Access Portal insecure deserialization flaw and Fireware Web UI issues.
WatchGuard published advisory WGSA-2026-00028 for a Firebox Management Web UI vulnerability involving arbitrary file write via path traversal. This is a separate disclosure from the previously tracked Access Portal and Web UI flaws.
WatchGuard published advisory WGSA-2026-00009 for CVE-2026-3987, a path traversal vulnerability in the Fireware OS Web UI that may let a privileged authenticated remote attacker achieve arbitrary code execution in an elevated system process. The flaw affects Fireware OS versions 12.6.1 through 12.11.8 and 2025.1 through 2026.1.2.
WatchGuard disclosed CVE-2026-4266, an insecure deserialization flaw in Fireware OS Access Portal that can lead to arbitrary code execution as the portald user. The issue affects Fireware OS versions 12.1 through 12.11.8 and 2025.1 through 2026.1.2, and requires prior local filesystem write access via another vulnerability.
Vulnerabilities, threat actors, malware, products, organizations, and breaches Mallory has linked to this story.
5 references tracked. Mallory keeps watching after this page renders.
watchguard.com
Open sourcewatchguard.com
Open sourcecyber.gc.ca
Open sourcecvefeed.io
Open sourcecvefeed.io
Open sourceMap indicators from this story to your assets and identify affected systems in minutes.
Every observed campaign, victim, and pivot linked to actors named in this story.
Malware, exploits, and IOCs connected to the activity described here.
YARA, Sigma, and Snort rules deployed to your SIEM as soon as they’re published.
Get matching new stories delivered to your team as they break — not the next morning.
Ask questions about this story and take action on the answers.
Other stories Mallory is tracking that overlap on entities, sources, or topic labels.
WatchGuard published security advisories for multiple **Fireware OS** vulnerabilities affecting **Firebox** appliances and related deployments, and the Canadian Centre for Cyber Security urged organizations to apply updates. The issues include an **out-of-bounds write** that could allow a privileged, authenticated administrator to achieve **root-level arbitrary code execution** via an exposed management interface (**CVE-2026-3342**), and a **filesystem integrity check bypass** that could allow an attacker to maintain **limited persistence** by using a maliciously crafted firmware update package (**CVE-2026-3344**). A separate advisory also notes a **reflected XSS** issue in the Fireware Web UI (**CVE-2026-3343**). Affected versions span multiple Fireware OS branches, including **12.0–12.11.7**, **12.5.9–12.5.16** (T15/T35 models), and **2025.1–2026.1.1**, with additional impact noted for **11.x** in the out-of-bounds write advisory (11.x is end-of-life). WatchGuard’s fixes are available in **12.11.8**, **12.5.17**, and **2026.1.2** (depending on branch/model), and no workaround was listed for the integrity-check bypass or out-of-bounds write issues; organizations should prioritize patching and ensure management interfaces are not unnecessarily exposed.
Jul 3, 2026
A critical vulnerability, tracked as CVE-2025-9242, has been discovered in WatchGuard's Fireware OS, affecting a wide range of Firebox network security appliances. This flaw is an out-of-bounds write in the 'iked' process, which is responsible for handling IKEv2 VPN negotiations. The vulnerability allows remote attackers to execute arbitrary code on affected devices without authentication, posing a severe risk to organizations relying on these appliances for network security. The issue specifically impacts devices configured with mobile user VPNs or branch office VPNs using IKEv2 with dynamic gateway peers. Security researchers have demonstrated that attackers can exploit this bug by sending specially crafted IKEv2 packets during the IKE_SA_AUTH phase, triggering a buffer overflow in the ike2_ProcessPayload_CERT function. Once exploited, attackers can gain control of the instruction pointer, establish Python interactive shells over TCP, and escalate to a full Linux shell by remounting filesystems and deploying BusyBox binaries. The vulnerability has been assigned a CVSS score of 9.3, underscoring its critical nature. According to scans by The Shadowserver Foundation, nearly 76,000 Firebox appliances remain exposed and vulnerable on the public internet, with the highest concentrations in the United States, Germany, Italy, the United Kingdom, Canada, and France. Affected Fireware OS versions include 11.10.2 through 11.12.4_Update1, the entire 12.0 series up to 12.11.3, and the 2025.1 release, impacting both older and newer Firebox models. WatchGuard has released patches in versions 12.3.1_Update3, 12.5.13, 12.11.4, and 2025.1.1 to address the vulnerability. Devices running version 11.x are no longer supported and will not receive security updates, prompting the vendor to recommend upgrading to a supported version. For appliances configured only with Branch Office VPNs to static gateway peers, WatchGuard has provided documentation for securing connections as a temporary workaround. The vulnerability transforms trusted security appliances into potential entry points for attackers, threatening the integrity of network defenses. Organizations are urged to assess their Firebox deployments, prioritize patching, and review VPN configurations to mitigate the risk. The widespread exposure of vulnerable devices highlights the urgency of remediation efforts. WatchGuard's disclosure and the subsequent public scanning have brought significant attention to the issue, emphasizing the importance of timely patch management in network security infrastructure. Failure to address this vulnerability could result in unauthorized access, lateral movement, and compromise of sensitive internal networks. The incident serves as a stark reminder of the risks posed by critical flaws in security appliances and the need for continuous monitoring and rapid response.
Jun 29, 2026
A critical zero-day vulnerability, identified as CVE-2025-14733, has been discovered in WatchGuard Firebox firewalls, allowing remote unauthenticated attackers to execute arbitrary code. The flaw, rated with a CVSS score of 9.3, resides in the `iked` process responsible for handling IKEv2 VPN connections, specifically affecting both Mobile User VPN and Branch Office VPN configurations. Attackers can exploit this out-of-bounds write vulnerability by sending specially crafted requests, potentially leading to full device compromise and firewall hijacking. WatchGuard has confirmed active exploitation of this vulnerability in the wild, with threat actors targeting exposed devices. Indicators of compromise include suspicious IP addresses, unusually large certificate payloads in IKE_AUTH requests, long certificate chains, and unexpected crashes of the `iked` process. Administrators are urged to apply the latest security updates immediately and review their logs for signs of compromise. The vulnerability affects Fireware OS versions 11.10.2 through 11.12.4_Update1, 12.0 through 12.11.5, and 2025.1 through 2025.1.3.
Jun 29, 2026