H2O
CVE-2016-4864
HIGH
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A05:2025 - Injection
ASVS 5.0
V1 - Encoding and Sanitization Format string safety
|
| Impact | CVSS score of 7.5 (HIGH). Attack characteristics: network attack vector, low complexity, no privileges required, no user interaction not required. EPSS exploitation probability: 1.60%. |
| Exploit ScenarioDerived | This vulnerability can be exploited remotely over the network. Successful exploitation could compromise the high-severity affected system. |
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Alert meAnalysisAI
H2O versions 2.0.3 and earlier and 2.1.0-beta2 and earlier allows remote attackers to cause a denial-of-service (DoS) via format string specifiers in a template file via fastcgi, mruby, proxy,. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
RemediationAI
A vendor patch is available. Apply the latest security update as soon as possible. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.
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Technical ContextAI · show details
This vulnerability is classified under CWE-134. H2O versions 2.0.3 and earlier and 2.1.0-beta2 and earlier allows remote attackers to cause a denial-of-service (DoS) via format string specifiers in a template file via fastcgi, mruby, proxy, redirect or reproxy. Affected products include: Dena H2O.
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionCVE.org
H2O versions 2.0.3 and earlier and 2.1.0-beta2 and earlier allows remote attackers to cause a denial-of-service (DoS) via format string specifiers in a template file via fastcgi, mruby, proxy, redirect or reproxy.
Threat Intelligence Overview
NVD
CVE.org
EPSS
GitHub
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Information disclosure occurs when an application unintentionally exposes sensitive data that aids attackers in reconnaissance or directly compromises security.
Affected Products (CPE)CVE.org
Denial of service against HTTP/2 server implementations allows remote unauthenticated attackers to exhaust server resour
A vulnerability in the h2oai/h2o-3 REST API versions 3.46.0.4 allows unauthenticated remote attackers to execute arbitra
A deserialization vulnerability exists in h2oai/h2o-3 versions <= 3.46.0.8, allowing attackers to read arbitrary system
An attacker is able to gain remote code execution on a server hosting the H2O dashboard through it's POJO model import f
H2O.ai H2O through 3.46.0.4 allows attackers to arbitrarily set the JDBC URL, leading to deserialization attacks, file r
In h2oai/h2o-3 version 3.46.0, the `/99/Models/{name}/json` endpoint allows for arbitrary file overwrite on the target s
External Control of File Name or Path in h2oai/h2o-3. Rated high severity (CVSS 8.2), this vulnerability is remotely exp
In h2oai/h2o-3 version 3.46.0.2, a vulnerability exists where uploading and repeatedly parsing a large GZIP file can cau
A vulnerability in the `/3/ParseSetup` endpoint of h2oai/h2o-3 version 3.46.0.1 allows for a denial of service (DoS) att
A vulnerability in the `/3/Parse` endpoint of h2oai/h2o-3 version 3.46.0.1 allows for a denial of service (DoS) attack.
A vulnerability in the `/3/ImportFiles` endpoint of h2oai/h2o-3 version 3.46.1 allows an attacker to cause a denial of s
In h2oai/h2o-3 version 3.46.0.1, the `run_tool` command exposes classes in the `water.tools` package through the `ast` p
Exploit-DB