CVE-2024-45403

HIGH EPSS 45.7%
Published Oct 11, 20241y ago · Modified Jun 17, 20261w ago
7.5 CVSS 3.1
High
Find Similar
Published Oct 11, 2024 1y ago
Last Modified Jun 17, 2026 1w ago

Description

h2o is an HTTP server with support for HTTP/1.x, HTTP/2 and HTTP/3. When h2o is configured as a reverse proxy and HTTP/3 requests are cancelled by the client, h2o might crash due to an assertion failure. The crash can be exploited by an attacker to mount a Denial-of-Service attack. By default, the h2o standalone server automatically restarts, minimizing the impact. However, HTTP requests that were served concurrently will still be disrupted. The vulnerability has been addressed in commit 1ed32b2. Users may disable the use of HTTP/3 to mitigate the issue.

CVSS Details

Base Score
7.5
Exploitability
3.9
Impact
3.6
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality None
Integrity None
Availability High

Threat Intelligence

EPSS Exploit Probability
45.7% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Weaknesses 1

CWE-617

Affected Products 1

VendorProductVersionRange
denah2o*≥2024-06-18  –  <2024-09-04

References 4

  • github.com https://github.com/h2o/h2o/commit/16b13eee8ad7895b4fe3fcbcabee53bd52782562
    Patch
  • github.com https://github.com/h2o/h2o/commit/1ed32b23f999acf0c5029f09c8525f93eb1d354c
    Patch
  • github.com https://github.com/h2o/h2o/security/advisories/GHSA-4xp5-3jhc-3m92
    Vendor Advisory
  • h2o.examp1e.net https://h2o.examp1e.net/configure/http3_directives.html
    Product

Remediation

  • github.com https://github.com/h2o/h2o/commit/16b13eee8ad7895b4fe3fcbcabee53bd52782562
    Patch
  • github.com https://github.com/h2o/h2o/commit/1ed32b23f999acf0c5029f09c8525f93eb1d354c
    Patch