CVE-2023-30847

H2O vulnerable to read from uninitialized pointer in the reverse proxy handler

Description

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.

Category

8.2
CVSS
Severity: High
CVSS 3.1 •
EPSS 0.26%
Vendor Advisory github.com Vendor Advisory github.com
Affected: h2o h2o
Published at:
Updated at:

References

Link Tags
https://github.com/h2o/h2o/security/advisories/GHSA-p5hj-phwj-hrvx patch vendor advisory
https://github.com/h2o/h2o/pull/3229 vendor advisory
https://github.com/h2o/h2o/commit/f010336bab162839df43d9e87570897466c97e33 patch

Frequently Asked Questions

What is the severity of CVE-2023-30847?
CVE-2023-30847 has been scored as a high severity vulnerability.
How to fix CVE-2023-30847?
To fix CVE-2023-30847, 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-2023-30847 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2023-30847 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-2023-30847?
CVE-2023-30847 affects h2o h2o.
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