CVE-2024-6863VulnerabilityPublished 20 Mar 2025Updated 15 Oct 2025

CVE-2024-6863: h2oai/h2o-3 · Exposed Dangerous Method or Function

Affects h2oai/h2o-3Source CVE Database V5

Not known to be exploited · CVSS 6.5 Medium.

Data as of 26 Oct 2026, 07:57 UTC

CVSS 3.0 base score

6.5Medium

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.3% chance of exploitation in 30 days – higher than 29% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: None
Integrity: Low
Availability: Low

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: None: There is no loss of confidentiality within the impacted component.
Integrity: Low: Modification of data is possible, but the attacker does not have control over the consequence of a modification, or the amount of modification is limited. The data modification does not have a direct, serious impact on the impacted component.
Availability: Low: Performance is reduced or there are interruptions in resource availability. Even if repeated exploitation of the vulnerability is possible, the attacker does not have the ability to completely deny service to legitimate users. The resources in the impacted component are either partially available all of the time, or fully available only some of the time, but overall there is no direct, serious consequence to the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 20 Mar 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-26.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Affected software

Product	Affected	Fixed in
GitHubh2oai/h2o-3`pkg:github/h2oai/h2o-3`Other threats	Affected =3.46.0	Fixed in–

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

1. Immediately restrict network access to the vulnerable EncryptionTool endpoint using firewall rules or network segmentation to limit exposure to trusted administrators only. 2. Implement strict authentication and authorization controls around all encryption-related functionalities to prevent unauthorized use. 3. Monitor logs and network traffic for unusual encryption activity or access patterns indicative of exploitation attempts. 4. If possible, disable or remove the exposed EncryptionTool endpoint until a vendor patch or update is available. 5. Regularly back up critical data and verify backup integrity to ensure recovery capability in case of encryption incidents. 6. Engage with h2oai vendor support to obtain patches or mitigations as they become available. 7. Conduct security code reviews and penetration testing focused on exposed APIs and endpoints to identify similar dangerous exposures. 8. Educate system administrators and security teams about this vulnerability and the importance of controlling access to encryption tools. 9. Deploy endpoint detection and response (EDR) solutions capable of detecting anomalous file encryption behaviors. 10. Consider applying application-layer firewalls or API gateways that can enforce granular access policies on exposed services.

Description

In h2oai/h2o-3 version 3.46.0, an endpoint exposing a custom EncryptionTool allows an attacker to encrypt any files on the target server with a key of their choosing. The chosen key can also be overwritten, resulting in ransomware-like behavior. This vulnerability makes it possible for an attacker to encrypt arbitrary files with keys of their choice, making it exceedingly difficult for the target to recover the keys needed for decryption.

Impact

For European organizations, the impact of CVE-2024-6863 can be severe, especially for those relying on h2oai/h2o-3 for AI, data analytics, or machine learning workloads. Successful exploitation can lead to unauthorized encryption of critical files, causing data integrity loss and operational downtime. This ransomware-like behavior can disrupt services, delay projects, and incur significant recovery costs. The inability to recover encrypted files without the attacker’s key can lead to permanent data loss or force organizations to pay ransoms. Industries with high data sensitivity such as finance, healthcare, and critical infrastructure are particularly vulnerable. The medium CVSS score underestimates the potential operational impact if exploited at scale. Additionally, the lack of authentication requirements increases the attack surface, making it easier for threat actors to target exposed servers remotely. European organizations with limited incident response capabilities or those lacking proper network segmentation may face amplified risks. The reputational damage and regulatory consequences under GDPR for data unavailability or loss further exacerbate the impact.

CWE-749Exposed Dangerous Method or Function (opens in a new tab)
Base weaknessLikelihood of exploit: LowOWASP Top 10 A01:2025: Broken Access Control (opens in a new tab)
The product provides an Applications Programming Interface (API) or similar interface for interaction with external actors, but the interface includes a dangerous method or function that is not properly restricted.
Architecture and Design
If you must expose a method, make sure to perform input validation on all arguments, limit access to authorized parties, and protect against all possible vulnerabilities.
Architecture and Design · Implementation · Attack Surface Reduction
Identify all exposed functionality. Explicitly list all functionality that must be exposed to some user or set of users. Identify which functionality may be: accessible to all users; restricted to a small set of privileged users; prevented from being directly accessible at all
OWASP Cheat Sheets
Third Party Javascript Management (opens in a new tab)
Authorization (opens in a new tab)
OWASP ASVS 4.0.3
V14.5.1 (opens in a new tab)
V10.1.1 (opens in a new tab)
V1.4.4 (opens in a new tab)
Attack patterns
WebView Injection (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

huntr.com/bounties/10f55937-0cba-4530-897f-2abf30ed5270 (opens in a new tab)

Community reviews

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 15 Oct 2025, 13:37 UTC

WeaknessesCWE-749

Technical details

References

Community reviews

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