WatchGuard Firebox and XTM Appliances Arbitrary Code Execution (CVE-2022-26318)
Published In CISA KEV since Sources: CVE.org
What is affected, what to do
On WatchGuard Firebox and XTM appliances, an unauthenticated user can execute arbitrary code, aka FBX-22786. This vulnerability impacts Fireware OS before 12.7.2_U2, 12.x before 12.1.3_U8, and 12.2.x through 12.5.x before 12.5.9_U2.
The vulnerability is being actively exploited; treat it as a priority. The available sources name no fixed version. Check the vendor guidance in the references below. Immediate actions, mitigation and detection rules are in the runbook below.
Conflicting version data — version display is hidden until the data is resolved.
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Metrics
9.8
Priority
XIEM Effective CVSS: highest available CVSS rating from NVD and vendor data.
Source: NVD, CVSS v3
9.8
CVSS v3
Severity Critical on the scale from 0 to 10.
Source: CVE.org
78.2 %
EPSS score
High — model estimates ≥ 50% chance of real-world exploitation within 30 days.
Source: FIRST EPSS, percentile 99.58
Show all metrics
- Severity
- Critical
Priority (0–325)
The priority score is a consolidated metric that condenses several individual signals into a single, action-guiding ranking: technical severity (CVSS), exploitation likelihood (EPSS), known-exploited status (KEV) and the context of the affected asset. The aim is to answer the only truly important question in vulnerability management: what first?
Read in glossary- 228.87 Methodology
Exploit maturity
An exploit is code or a technique that specifically uses a concrete vulnerability to force unintended behaviour — such as executing code or escalating privileges. It is the tool that turns a theoretical flaw into a practical attack.
Read in glossary- actively exploited
XIEM Effective CVSS
XIEM® is the tiered managed-security operating model from NEOSEC and a registered trademark of NEOSEC GmbH. It extends classic SIEM — the central collection, normalisation and correlation of security-relevant events — with endpoint forensics, network visibility and deception technology, and consolidates them into three building tiers: Sentry, Orchestrate and Command.
Read in glossary- 9.8 Methodology
CVSS v3
CVSS is the globally established, open standard for assessing the technical severity of a vulnerability on a scale from 0 to 10. It describes how easily a flaw can be exploited and what damage it can cause — but not how likely its actual exploitation is. CVSS and the complementary EPSS deliberately answer different questions.
Read in glossary- 9.8
EPSS score
The EPSS score is the absolute model output for an individual vulnerability: the estimated probability of real-world exploitation within the next 30 days, expressed as a value between 0 and 1 (i.e. 0 % to 100 %). A score of 0.42 means „the model estimates a 42 % chance of real-world exploitation within 30 days“.
Read in glossary- 78.2 %
- High — model estimates ≥ 50% chance of real-world exploitation within 30 days.
EPSS percentile
The EPSS percentile is the relative position of a vulnerability within all EPSS-scored CVEs, expressed as a value between 0 and 1. A percentile of 0.90 means „this CVE has a higher EPSS score than 90 % of all other scored CVEs“. Unlike the EPSS score, it is not a probability — but a positioning within a ranking.
Read in glossary- 99.58
- Critical — this CVE ranks in the top fifth of all CVEs scored today (rank ≥ 80%).
KEV status
The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching.
Read in glossary- Actively exploited
- Published
In CISA KEV since
The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching.
Read in glossary
Response and mitigation
Why act now?
Prioritisation rationale
This flaw gives an unauthenticated attacker network-reachable code execution on a perimeter device that is exposed by design and controls all traffic and VPN access. A compromised firewall gives attackers persistence outside EDR visibility, a vantage point for harvesting credentials, and a direct path into the internal network. Public exploit code exists, and the likelihood of exploitation is among the highest of any CVE. Typical targets are SMEs and branch offices that left the management interface reachable from the internet. Treat any Firebox with an externally reachable Web UI as critical and act immediately, even though CISA does not flag known ransomware use. Devices whose management is internal-only should be upgraded within your standard emergency patch window of a few days.
Runbook step 1
Immediate response (0-24 h)
- Inventory now: Enumerate every WatchGuard Firebox and XTM appliance and record its Fireware OS version. Vulnerable versions are those before 12.7.2_U2, 12.x before 12.1.3_U8, and 12.2.x through 12.5.x before 12.5.9_U2 (vendor reference FBX-22786).
- Patch: Upgrade to Fireware OS 12.7.2_U2, 12.5.9_U2 or 12.1.3_U8 (or later). End-of-life XTM models with no fixed release should be treated as unpatchable and scheduled for replacement.
- Pull management off the internet immediately: Restrict the "WatchGuard Web UI" and "WatchGuard" management policies to trusted internal admin subnets. By default this covers TCP 8080 (Web UI) and TCP 4105/4117/4118 (WSM). Remove any "Any-External" source from these policies.
- Assess for compromise before patching: Preserve the configuration and logs before upgrading. If the management interface was internet-exposed, assume possible compromise, because an upgrade alone does not reliably remove persistence.
- Rotate secrets: For any exposed device, rotate everything stored on it. That includes admin and status passwords, VPN PSKs, certificates and private keys, LDAP/RADIUS bind accounts, and SNMP communities.
- If indicators are present: Factory-reset the device, install the patched firmware cleanly, and rebuild the configuration from a reviewed baseline. Do not restore a backup taken from the compromised state without review.
Runbook step 2
Mitigation layers
- Network segmentation: Make management interfaces reachable only from a dedicated admin VLAN or jump host. Allow remote administration only through a separate, MFA-protected VPN that terminates on a different endpoint.
- Upstream filtering: Where an upstream router or ISP ACL exists, drop inbound TCP 8080 and 4105/4117/4118 to the firewall's external IP. Allow only explicitly approved admin source IPs.
- IPS / network detection: On upstream sensors, deploy a signature for HTTP POSTs to the Web UI's
/agent/loginthat carry an abnormally large XML body. A Suricata sketch:http.method; content:"POST"; http.uri; content:"/agent/login"; dsize:>1500;. Run it in alert mode first, then switch to blocking after tuning. - Appliance hardening: Disable management services you don't use, and enable cloud management or Web UI access only where needed. Use named, role-based admin accounts rather than the default "admin" account.
- Lifecycle: Prioritise replacing unsupported XTM hardware. Until it is replaced, confine management strictly to internal interfaces and record the residual risk formally in the ISMS (ISO 27001 A.8.8).
Runbook step 3
Detection rules
- Management web access: In Firebox traffic logs or Zeek
http.log, look for POSTs to/agent/loginfrom external sources, especially those with a largerequest_body_len. SPL:index=fw dest_port IN (8080,4117) uri_path="/agent/login" NOT src_ip IN (admin_nets) | stats count by src_ip. - Appliance-originated outbound traffic: A firewall rarely initiates its own connections beyond updates, NTP, DNS, logging and WatchGuard cloud services. Hunt in Netflow or Zeek
conn.logfor sessions sourced from the firewall's own IPs to unfamiliar destinations, such as reverse shells on unusual ports. - Management events in syslog/Dimension: Watch for unexpected admin logins, newly created admin accounts, and policy or config changes outside change windows. Also flag crashes and restarts of the
wgagentprocess and unplanned reboots, since awgagentcrash can indicate failed exploitation attempts. - Configuration drift: Diff the running configuration against the last known-good baseline. Look for new NAT rules, opened management policies, new VPN peers, and changed DNS or syslog targets.
- Threat-intel correlation: Match external source IPs that hit the management ports against current scanner and botnet feeds. Treat any pre-patch hits as potential compromise and triage them forensically.
- Management web access: In Firebox traffic logs or Zeek
Detection rules
No NEOSEC detection rule is available for this vulnerability yet.
Classification under NIS2 and CRA
Rule-based classification from exploitation status and severity. It does not replace a case-by-case assessment.
NIS2
NIS2 is EU Directive (EU) 2022/2555 to raise the level of cybersecurity across the Union. It substantially broadens obligations compared with the first NIS directive: more sectors, mandatory risk management, staged reporting duties and personal accountability of senior management.
Read in glossary- Actively exploited: treat the vulnerability as a priority in vulnerability handling under Art. 21(2)(e) NIS2. If it is exploited in your environment, check the reporting obligation under Art. 23 (early warning within 24 hours).
CRA
The CRA is EU Regulation (EU) 2024/2847 setting horizontal cybersecurity requirements for „products with digital elements“ — from industrial controllers and software to connected consumer devices. For the first time manufacturers must ensure security across the entire product lifecycle, handle vulnerabilities and provide security updates.
Read in glossary- Since 11.09.2026, manufacturers of affected products with digital elements must report actively exploited vulnerabilities under Art. 14 CRA, with an early warning within 24 hours via ENISA's single reporting platform.
ISO/IEC 27001
ISO/IEC 27001 is the internationally leading standard for an information security management system (ISMS). It describes a risk-based, process-oriented framework to systematically plan, implement, review and improve information security.
Read in glossary- Control A.8.8, management of technical vulnerabilities: assess relevance to your systems, plan remediation and keep evidence.
Description
On WatchGuard Firebox and XTM appliances, an unauthenticated user can execute arbitrary code, aka FBX-22786. This vulnerability impacts Fireware OS before 12.7.2_U2, 12.x before 12.1.3_U8, and 12.2.x through 12.5.x before 12.5.9_U2.
Source: NVD (NIST), cvelistv5, CISA KEV Catalog, CVE.org (MITRE)
Vendors and products
Affected operating systems
| Other | watchguard | fireware | 12.1.3 |
| Other | watchguard | fireware | 12.5.9 |
| Other | watchguard | fireware | 12.7.2 |
| Other | watchguard | fireware | — |
Public exploit references
Publicly reported proof-of-concepts, exploit modules and detection templates for this vulnerability. NEOSEC links to the original sources only and does not provide any exploit code.
| CISA KEV Catalog | CISA Known Exploited Vulnerability (opens in a new tab)cisa.gov | actively exploited |
References & sources
- watchguard.comsupport/release-notes/fireware/12/en-US/EN_ReleaseNotes_Firewar…x_refsource_CONFIRM, Release notes, Vendor advisory
- cisa.govknown-exploited-vulnerabilities-catalog?field_cve=CVE-2022-26318government-resource, US government resource
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<a href="https://intel.neosec.eu/en/cve/CVE-2022-26318"><img src="https://intel.neosec.eu/badge/cve/CVE-2022-26318.svg?lang=en" alt="CVE-2022-26318 – NEOSEC Intel" height="20"></a>