H2O up to 2.3.0-beta2 Reverse Proxy uninitialized pointer

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.
CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
7.2$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as critical, has been found in H2O up to 2.3.0-beta2. This impacts an unknown function of the component Reverse Proxy Handler. This manipulation causes uninitialized pointer. The identification of this vulnerability is CVE-2023-30847. It is possible to initiate the attack remotely. There is no exploit available. It is recommended to apply a patch to fix this issue.

Detailsinfo

A vulnerability was found in H2O up to 2.3.0-beta2. It has been declared as critical. Affected by this vulnerability is an unknown functionality of the component Reverse Proxy Handler. The manipulation with an unknown input leads to a uninitialized pointer vulnerability. The CWE definition for the vulnerability is CWE-824. The product accesses or uses a pointer that has not been initialized. As an impact it is known to affect confidentiality, and availability. The summary by CVE is:

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.

The weakness was shared 04/27/2023 as GHSA-p5hj-phwj-hrvx. It is possible to read the advisory at github.com. This vulnerability is known as CVE-2023-30847 since 04/18/2023. The technical details are unknown and an exploit is not publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 253190 (Linux Distros Unpatched Vulnerability : CVE-2023-30847), which helps to determine the existence of the flaw in a target environment.

Applying the patch f010336bab162839df43d9e87570897466c97e33 is able to eliminate this problem. The bugfix is ready for download at github.com.

The vulnerability is also documented in the vulnerability database at Tenable (253190). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.3
VulDB Meta Temp Score: 7.2

VulDB Base Score: 6.5
VulDB Temp Score: 6.2
VulDB Vector: 🔍
VulDB Reliability: 🔍

CNA Base Score: 8.2
CNA Vector (GitHub, Inc.): 🔍

CVSSv2info

AVACAuCIA
💳💳💳💳💳💳
💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock

VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Uninitialized pointer
CWE: CWE-824 / CWE-908
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-DayUnlockUnlockUnlockUnlock
TodayUnlockUnlockUnlockUnlock

Nessus ID: 253190
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2023-30847

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔍

Patch: f010336bab162839df43d9e87570897466c97e33

Timelineinfo

04/18/2023 🔍
04/27/2023 +9 days 🔍
04/27/2023 +0 days 🔍
08/25/2025 +851 days 🔍

Sourcesinfo

Product: github.com

Advisory: GHSA-p5hj-phwj-hrvx
Status: Confirmed

CVE: CVE-2023-30847 (🔍)
GCVE (CVE): GCVE-0-2023-30847
GCVE (VulDB): GCVE-100-227599

Entryinfo

Created: 04/27/2023 20:25
Updated: 08/25/2025 08:12
Changes: 04/27/2023 20:25 (50), 08/25/2025 08:12 (17)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

Discussion

No comments yet. Languages: en.

Please log in to comment.

◂ PreviousOverviewNext ▸

Might our Artificial Intelligence support you?

Check our Alexa App!