Vulnerability in Dena H2o

CVE-2024-45397

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.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.004 (35.8th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 36th percentile — 35.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2024-45397: held from 0.004 to 0.004.

EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000

Affected products

  • Dena H2o
  • H2o — versions < 15ed15a2efb83a77bb4baaa5a119e639c2f6898a

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2024-45397?
CVE-2024-45397 is a medium-severity vulnerability in Dena H2o, classified under Improper Access Control. CVSS score: 5.9/10. Published 2024-10-11.
How severe is CVE-2024-45397?
Medium severity. CVSS v3 base score is 5.9 out of 10.
Is CVE-2024-45397 known to be exploited?
2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.