CVE-2024-56516: MD5 hashing — UNKNOWN

CISO Take

free-one-api uses MD5 to hash passwords before backend transmission—a broken algorithm crackable in seconds with commodity hardware and rainbow tables. No patch has been committed as of publication date. If you have any internet-exposed instance, treat credentials as compromised: restrict access to localhost/VPN-only and rotate all configured API keys immediately.

What is the risk?

Despite the absent CVSS score, operational risk is HIGH for any internet-exposed deployment. MD5 provides zero meaningful password protection—common passwords fall to precomputed rainbow tables instantly, and GPU cracking handles the rest. The blast radius extends beyond the tool itself: free-one-api stores API keys for underlying LLM providers, so a single cracked admin password cascades to full LLM API access. Exploitation requires no AI/ML knowledge, only standard credential-cracking tooling available to any script-kiddie.

How severe is it?

CVSS 3.1

N/A

EPSS

0.3%

chance of exploitation in 30 days

Higher than 24% of all CVEs

Source: EPSS v3 — FIRST.org

Exploitation Status

No known exploitation

Sophistication

Trivial

What should I do?

5 steps

Immediately restrict the free-one-api admin interface to localhost or a trusted internal network—no public internet exposure.
Rotate all credentials (admin passwords and any backend API keys stored in the tool).
Audit access logs for anomalous logins or unexpected LLM usage spikes.
If possible, migrate to an alternative LLM proxy that implements bcrypt, Argon2, or scrypt for password hashing.
Monitor RockChinQ/free-one-api on GitHub for a patch release; issue is unresolved as of 2024-12-30. Detection: alert on repeated failed logins to the admin endpoint and unexpected API key usage from unfamiliar IPs.

What does CISA's SSVC say?

Decision Track*

Exploitation none

Automatable Yes

Technical Impact total

Source: CISA Vulnrichment (SSVC v2.0). Decision based on the CISA Coordinator decision tree.

How is it classified?

Auth Bypass Data Extraction API Framework AML.T0012 - Valid Accounts AML.T0034 - Cost Harvesting AML.T0040 - AI Model Inference API Access AML.T0055 - Unsecured Credentials

Which compliance frameworks are affected?

This CVE is relevant to:

EU AI Act

Article 9 - Risk management system

ISO 42001

A.6.2.6 - AI system security

NIST AI RMF

GOVERN-1.4 - Organizational risk management processes

OWASP LLM Top 10

LLM05:2025 - Improper Output Handling / Supply Chain Vulnerabilities

Frequently Asked Questions

What is CVE-2024-56516?

free-one-api uses MD5 to hash passwords before backend transmission—a broken algorithm crackable in seconds with commodity hardware and rainbow tables. No patch has been committed as of publication date. If you have any internet-exposed instance, treat credentials as compromised: restrict access to localhost/VPN-only and rotate all configured API keys immediately.

Is CVE-2024-56516 actively exploited?

No confirmed active exploitation of CVE-2024-56516 has been reported, but organizations should still patch proactively.

How to fix CVE-2024-56516?

1. Immediately restrict the free-one-api admin interface to localhost or a trusted internal network—no public internet exposure. 2. Rotate all credentials (admin passwords and any backend API keys stored in the tool). 3. Audit access logs for anomalous logins or unexpected LLM usage spikes. 4. If possible, migrate to an alternative LLM proxy that implements bcrypt, Argon2, or scrypt for password hashing. 5. Monitor RockChinQ/free-one-api on GitHub for a patch release; issue is unresolved as of 2024-12-30. Detection: alert on repeated failed logins to the admin endpoint and unexpected API key usage from unfamiliar IPs.

What systems are affected by CVE-2024-56516?

This vulnerability affects the following AI/ML architecture patterns: model serving, agent frameworks, LLM API gateway.

What is the CVSS score for CVE-2024-56516?

No CVSS score has been assigned yet.

What is the AI security impact?

Affected AI Architectures

model servingagent frameworksLLM API gateway

MITRE ATLAS Techniques

AML.T0012 Valid Accounts

AML.T0034 Cost Harvesting

AML.T0040 AI Model Inference API Access

AML.T0055 Unsecured Credentials

Compliance Controls Affected

EU AI Act: Article 9

ISO 42001: A.6.2.6

NIST AI RMF: GOVERN-1.4

OWASP LLM Top 10: LLM05:2025

What are the technical details?

Original Advisory

free-one-api allows users to access large language model reverse engineering libraries through the standard OpenAI API format. In versions up to and including 1.0.1, MD5 is used to hash passwords before sending them to the backend. MD5 is a cryptographically broken hashing algorithm and is no longer considered secure for password storage or transmission. It is vulnerable to collision attacks and can be easily cracked using modern hardware, exposing user credentials to potential compromise. As of time of publication, a replacement for MD5 has not been committed to the free-one-api GitHub repository.

Exploitation Scenario

An attacker targeting an internet-exposed free-one-api instance intercepts the login request via network sniffing or obtains a leaked database dump containing MD5-hashed admin passwords. Using Hashcat with the rockyou wordlist on consumer GPU hardware, the plaintext password is recovered in under a minute for common passwords. The attacker authenticates to the admin panel, exfiltrates stored LLM API keys (OpenAI, Anthropic, etc.), and gains persistent access to the proxy. From this position they can silently log all prompts and responses flowing through the proxy, rack up API costs via the victim's keys, or use the foothold for lateral movement to other internal services.

Weaknesses (CWE)

CWE-328 Use of Weak Hash

CWE-328 — Use of Weak Hash: The product uses an algorithm that produces a digest (output value) that does not meet security expectations for a hash function that allows an adversary to reasonably determine the original input (preimage attack), find another input that can produce the same hash (2nd preimage attack), or find multiple inputs that evaluate to the same hash (birthday attack).

[Architecture and Design] Use an adaptive hash function that can be configured to change the amount of computational effort needed to compute the hash, such as the number of iterations ("stretching") or the amount of memory required. Some hash functions perform salting automatically. These functions can significantly increase the overhead for a brute force attack compared to intentionally-fast functions such as MD5. For example, rainbow table attacks can become infeasible due to the high computing overhead. Finally, since computing power gets faster and cheaper over time, the technique can be reconfigured to increase the workload without forcing an entire replacement of the algorithm in use. Some hash functions that have one or more of these desired properties include bcrypt [REF-291], scrypt [REF-292], and PBKDF2 [REF-293]. While there is active debate about which of these is the most effective, they are all stronger than using salts with hash functions with very little computing overhead. Note that using thes

Source: MITRE CWE corpus.