CVE-2023-30847

Memory Safety in Dena H2O ≤ 2.2.6

Memory Safety

Published

27 April 2023

Modified

21 November 2024

Patch / advisory

View advisory

CVSS Score v3.1 8.2

Click a component to see what it means

Raw vector

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

EPSS Score 0.0090 57th percentile

Risk Priority 63 floored blend · peak EPSS

Summary

CVE-2023-30847 is a high-severity Access of Uninitialized Pointer (CWE-824) vulnerability in Dena H2O. Its CVSS base score is 8.2 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked in the top 43% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

🇪🇺 ENISA EUVD: EUVD-2023-35199

Vulnerability Data

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.

CWE(s): CWE-824

Related Threats

MITRE ATT&CK Enterprise Techniques

T1068 Exploitation for Privilege Escalation Privilege Escalation

Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.

attack.mitre.org →

T1190 Exploit Public-Facing Application Initial Access

Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.

attack.mitre.org →

T1203 Exploitation for Client Execution Execution

Adversaries may exploit software vulnerabilities in client applications to execute code.

attack.mitre.org →

T1210 Exploitation of Remote Services Lateral Movement

Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.

attack.mitre.org →

T1211 Exploitation for Stealth Stealth

Adversaries may exploit vulnerabilities to evade detection by hiding activity, suppressing logging, or operating within trusted or unmonitored components.

attack.mitre.org →

T1212 Exploitation for Credential Access Credential Access

Adversaries may exploit software vulnerabilities in an attempt to collect credentials.

attack.mitre.org →

Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2024-45397Same product: Dena H2O

CVE-2024-25622Same product: Dena H2O

CVE-2024-45403Same product: Dena H2O

CVE-2023-50247Same product: Dena H2O

CVE-2023-41337Same product: Dena H2O

CVE-2024-9258Shared CWE-824

CVE-2025-1761Shared CWE-824

CVE-2024-8645Shared CWE-824

CVE-2025-47098Shared CWE-824

CVE-2025-43557Shared CWE-824

Affected Assets

dena

h2o

2.3.0 · ≤ 2.2.6

Mitigating Controls

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match

prevents

Secure SDLC practices directly prevent uninitialized pointer bugs via coding standards, analysis, and reviews, but eliminating this single weakness only partially fulfills the broader control.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.8.29 Security testing in development and acceptance mostly match

finds

Security testing can detect uninitialized pointer usage before release.

A.8.25 Secure development life cycle partial match

prevents

Secure development life cycle mandates practices that reduce uninitialized pointer defects.

A.8.26 Application security requirements partial match

degrades

Application security requirements can specify pointer initialization rules.

A.8.27 Secure system architecture and engineering principles partial match

degrades

Secure architecture principles discourage unsafe pointer handling.