CVE-2023-30847 - CVE House
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Status published High CVE-2023-30847

H2O vulnerable to read from uninitialized pointer in the reverse proxy handler

Vulnerability Description

H2O is an HTTP server. In versions 2.3.0-beta2 and prior, when the reverse proxy handler tries to processes a certain type of invalid HTTP request, it tries to build an upstream URL by reading from uninitialized pointer. This behavior can lead to crashes or leak of information to back end HTTP servers. Pull request number 3229 fixes the issue. The pull request has been merged to the `master` branch in commit f010336. Users should upgrade to commit f010336 or later.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

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Affected Vendor

Affected Software

h2o
Vulnerable Versions:
<= 2.3.0-beta2

Timeline

Official Publish: April 27th, 2023
Last Modified: January 30th, 2025
Added to House: July 22nd, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H

Weaknesses (CWE)

CWE-824

MITRE ATT&CK TTPs

T1203 Exploitation for Client Execution
Execution
T1068 Exploitation for Privilege Escalation
Privilege Escalation