---
title: "CVE-2024-45397\n    | Ubuntu"
description: Ubuntu is an open source software operating system that runs from the
  desktop, to the cloud, to all your internet connected things.
url: https://ubuntu.com/security/CVE-2024-45397?format=md
keywords: index, follow
---

# CVE-2024-45397

Publication date 11 October 2024

Last updated 11 July 2025

---

Ubuntu priority

**Medium**

[Why this priority?](https://ubuntu.com/security/cves/about#priority )

## Cvss 3 Severity Score

**5.9 · Medium**

[Score breakdown](https://ubuntu.com/security/CVE-2024-45397?format=md#impact-score)

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## Description

h2o is an HTTP server with support for HTTP/1.x, HTTP/2 and HTTP/3. When an
HTTP request using TLS/1.3 early data on top of TCP Fast Open or QUIC 0-RTT
packets is received and the IP-address-based access control is used, the
access control does not detect and prohibit HTTP requests conveyed by
packets with a spoofed source address. This behavior allows attackers on
the network to execute HTTP requests from addresses that are otherwise
rejected by the address-based access control. The vulnerability has been
addressed in commit 15ed15a. Users may disable the use of TCP FastOpen and
QUIC to mitigate the issue.

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| h2o | 26.04 LTS resolute | Not in release |
| 25.10 questing | Not in release |
| 25.04 plucky | Ignored end of life, was needs-triage |
| 24.10 oracular | Ignored end of life, was needs-triage |
| 24.04 LTS noble | Needs evaluation |
| 22.04 LTS jammy | Needs evaluation |
| 20.04 LTS focal | Ignored end of standard support, was needs-triage |
| 18.04 LTS bionic | Needs evaluation |

---

* [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)
* [What do statuses mean?](https://ubuntu.com/security/cves/about#statuses)

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

5.9 · Medium

* Base metrics

  | Parameter | Value |
  | --- | --- |
  | Attack vector | Network |
  | Attack complexity | High |
  | Privileges required | None |
  | User interaction | None |
  | Scope | Unchanged |
  | Confidentiality impact | High |
  | Integrity impact | None |
  | Availability impact | None |
* Scores

  | Parameter | Value |
  | --- | --- |
  | Base score | 5.9 · Medium |
  | Exploitability score | - |
  | Impact score | - |

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

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2024-45397)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2024-45397)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2024-45397)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2024-45397)

### Other references

* <https://www.cve.org/CVERecord?id=CVE-2024-45397>
* <https://github.com/h2o/h2o/security/advisories/GHSA-jf2c-xjcp-wg4c>
* <https://github.com/h2o/h2o/commit/15ed15a2efb83a77bb4baaa5a119e639c2f6898a>
* <https://h2o.examp1e.net/configure/http3_directives.html>