What it is
CVE-2025-54123 is an unauthenticated vulnerability affecting SpectoLabs hoverfly. Hoverfly is an open source API simulation tool. In versions 1.11.3 and prior, the middleware functionality in Hoverfly is vulnerable to...
Vulnerability report
Exploited in the wild
High confidence
Not in CISA KEV
CVE-2025-54123
hoverfly Remote Code Execution
SpectoLabs / hoverfly · <= 1.11.3
- Severity
- CVSS 9.8 · Critical
- Confidence
- High
- Exploit status
- Exploited in the wild
- EPSS
- 10.5%
- First observed
- —
- Last observed
- —
Decision summary
What security teams need to know first
Direct answers before the deeper technical record.
Is it exploited?
Yes. KEV Intelligence tracks this CVE as a known exploited vulnerability. Confidence is high.
Who is affected?
SpectoLabs / hoverfly <= 1.11.3.
What should we do?
Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.
Overview
Hoverfly is an open source API simulation tool
Hoverfly is an open source API simulation tool. In versions 1.11.3 and prior, the middleware functionality in Hoverfly is vulnerable to command injection vulnerability at `/api/v2/hoverfly/middleware` endpoint due to insufficient validation and sanitization in user input. The vulnerability exists in the middleware management API endpoint `/api/v2/hoverfly/middleware`. This issue is born due to combination of three code level flaws: Insufficient Input Validation in middleware.go line 94-96; Unsafe Command Execution in local_middleware.go line 14-19; and Immediate Execution During Testing in hoverfly_service.go line 173.
This allows an attacker to gain remote code execution (RCE) on any system running the vulnerable Hoverfly service. Since the input is directly passed to system commands without proper checks, an attacker can upload a malicious payload or directly execute arbitrary commands (including reverse shells) on the host server with the privileges of the Hoverfly process. Commit 17e60a9bc78826deb4b782dca1c1abd3dbe60d40 in version 1.12.0 disables the set middleware API by default, and subsequent changes to documentation make users aware of the security changes of exposing the set middleware API.
Vendor
Product
Affected
Status
SpectoLabs
hoverfly
<= 1.11.3
Affected
- Published
- 10 Sep 2025
- Exploitation Reported
- 11 Nov 2025
- Attack vector
- Remote
- Complexity
- Low
- Privileges
- None
- User interaction
- None
Tags
nuclei_scanner
CVE References
- CVE Record CVE.org · CVE Record https://www.cve.org/CVERecord?id=CVE-2025-54123
- https://github.com/SpectoLabs/hoverfly/security/advisories/GHSA-r4h8-hfp2-ggmf github.com · CVE Record https://github.com/SpectoLabs/hoverfly/security/advisories/GHSA-r4h8-...
- https://github.com/SpectoLabs/hoverfly/commit/17e60a9bc78826deb4b782dca1c1abd3dbe60d40 github.com · CVE Record https://github.com/SpectoLabs/hoverfly/commit/17e60a9bc78826deb4b782d...
- https://github.com/SpectoLabs/hoverfly/commit/a9d4da7bd7269651f54542ab790d0c613d568d3e github.com · CVE Record https://github.com/SpectoLabs/hoverfly/commit/a9d4da7bd7269651f54542a...
- https://github.com/SpectoLabs/hoverfly/blob/master/core/hoverfly_service.go#L173 github.com · CVE Record https://github.com/SpectoLabs/hoverfly/blob/master/core/hoverfly_serv...
- https://github.com/SpectoLabs/hoverfly/blob/master/core/middleware/local_middleware.go#L13 github.com · CVE Record https://github.com/SpectoLabs/hoverfly/blob/master/core/middleware/lo...
- https://github.com/SpectoLabs/hoverfly/blob/master/core/middleware/middleware.go#L93 github.com · CVE Record https://github.com/SpectoLabs/hoverfly/blob/master/core/middleware/mi...
Exploitation evidence
Why KEV Intelligence marks this CVE as exploited
Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.
Exploited in the wild
The Shadowserver
Independent exploitation attestation added to the KEV Intelligence record.
Proof of concept available
Nuclei Templates
Public scanner or PoC coverage increases practical exploitability.
Known exploited vulnerability sources
Per-source evidence links for KEV attestations are available through the KEV Intelligence Pro API.
Learn about Pro API access| Source | Added |
|---|---|
| The Shadowserver First | 2025-11-11 00:00 UTC |
Detection
Operational artifacts and observed signals
Make the evidence actionable in scanner, SOC, and edge-control workflows.
Observed signals
- Request targets
- 0
- User-Agents
- 0
Raw values available in Pro and Enterprise.
Scanner coverage
Nuclei template detected 01 Jun 2026.
View Nuclei template (opens in new tab)Virtual patch status
No KEV Intelligence virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.
Learn about virtual patches →Scanner Artifacts
Scanner and exploit-framework references linked to this CVE.
| Scanner | Reference | Detected |
|---|---|---|
| Nuclei | https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2025/CVE-2025-54123.yaml | 01 Jun 2026 |
Risk and context
Severity, weaknesses, and research context
CVSS v3.1
9.8
Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
10.5%
Potential Proof of Concepts
These PoCs are unverified and could contain malware. Use at your own risk.
Hoverfly <= 1.11.3 - Remote Code Execution
nuclei · Created Unknown
Timeline
From disclosure to observed exploitation
-
Public PoC available
Public proof-of-concept code published
-
Nuclei template available
Scanner coverage available
-
Added to KEV Intelligence KEV Feed
High-confidence, third-party attested exploitation
-
CVE published
Vulnerability disclosed publicly
-
CVE ID reserved
Identifier reserved by the CNA
Pro API
Automate this intelligence
Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.
- Evidence confidence and provenance
- First-party sensor telemetry
- PoC and scanner references
- Affected versions and enrichment
- Automation-ready JSON delivery
GET /api/v2/pro/kevs/CVE-2025-54123
Free JSON includes basic KEV fields{
"cve_id": "CVE-2025-54123",
"confidence": "High",
"cvss_score": 9.8,
"cvss_estimated": false,
"epss_score": 0.10543,
"exploit_status": {
"exploited_in_the_wild": true,
"active_exploitation_observed": false
},
"sensor_telemetry": { "attempts": 0, "sensors": 0 }
}Early warning alerts
Get alerts on high-impact exploitation
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