CVE-2024-45397

H2O alllows bypassing address-based access control with 0-RTT

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.

Categories

5.9
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.09%
Vendor Advisory github.com
Affected: h2o h2o
Published at:
Updated at:

References

Link Tags
https://github.com/h2o/h2o/security/advisories/GHSA-jf2c-xjcp-wg4c vendor advisory
https://github.com/h2o/h2o/commit/15ed15a2efb83a77bb4baaa5a119e639c2f6898a patch
https://h2o.examp1e.net/configure/http3_directives.html product

Frequently Asked Questions

What is the severity of CVE-2024-45397?
CVE-2024-45397 has been scored as a medium severity vulnerability.
How to fix CVE-2024-45397?
To fix CVE-2024-45397, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2024-45397 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2024-45397 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2024-45397?
CVE-2024-45397 affects h2o h2o.
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