RCE in Hoverfly

CVE-2025-54123

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.

Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.105 (95.6th percentile), scored .

Moderate probability of exploitation in the next 30 days — watch for active exploitation reports. 96th percentile — 95.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2025-54123: held from 0.105 to 0.105.

EPSS over last 30 days · oldest: 0.105 · newest: 0.105 · change: 0.000

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2025-54123?
CVE-2025-54123 is a critical-severity vulnerability in Hoverfly, classified under Improper Input Validation. CVSS score: 9.8/10. Published 2025-09-10.
How severe is CVE-2025-54123?
Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2025-54123 known to be exploited?
11 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.