Vulnerability · Published Feb 2, 2026 · Assigned by @huntr_ai
CVE-2024-5986Remote Arbitrary File Write with Arbitrary Data in h2oai/h2o-3
Critical 9.1
In plain English
A critical-severity security flaw in h2oai/h2o-3 from h2oai. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.7% (higher than 53% of all known vulnerabilities).
Official description
A vulnerability in h2oai/h2o-3 version 3.46.0.1 allows remote attackers to write arbitrary data to any file on the server. This is achieved by exploiting the `/3/Parse` endpoint to inject attacker-controlled data as the header of an empty file, which is then exported using the `/3/Frames/framename/export` endpoint. The impact of this vulnerability includes the potential for remote code execution and complete access to the system running h2o-3, as attackers can overwrite critical files such as private SSH keys or script files.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Maven | ai.h2o:h2o-core | no fix listed | GHSA-wj3h-wx8g-x699 |
| PyPI | h2o | no fix listed | GHSA-wj3h-wx8g-x699 |
| PyPI | h2o | no fix listed | PYSEC-2026-353 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| h2oai | h2oai/h2o-3 | unspecified – through latest |
Weakness: CWE-73 · Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H