CVE-2025-54123 | Hoverfly vulnerable to remote code execution at `/api/v2/hoverfly/middleware` endpoint due to insecure middleware implementation

Exp

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.

Published: 2025-09-10 Last update: 2025-09-17 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2025-54123 is rated High Exploit Risk (87/100): CVSS Critical severity, with high exploitation likelihood (EPSS 50.93%, 98th percentile). Core evidence: 1 public exploit reference(s) are indexed (Exploit-DB). Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2025-54123

EDB-ID Source Kind Published Link
nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2025-54123

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-31 52.39% 50.93% -1.46%
2 2026-05-27 59.02% 52.39% -6.63%
3 2026-05-25 59.02%

Full EPSS history (30 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-54123

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
3.9 5.9 [email protected]

Weakness enumeration for CVE-2025-54123

GitHub Security Advisory for CVE-2025-54123

GHSA-r4h8-hfp2-ggmf · Severity: critical · Ecosystem: go — Hoverfly is vulnerable to Remote Code Execution through an insecure middleware implementation

Affected software / configurations for CVE-2025-54123

Vendor Product Version Raw CPE
hoverfly hoverfly < 1.12.0 cpe:2.3:a:hoverfly:hoverfly:*:*:*:*:*:*:*:*

References for CVE-2025-54123

cvelogic Threat Intelligence