CVE-2023-28111

Discourse vulnerable to SSRF protection bypass possible with IPv4-mapped IPv6 addresses

Description

Discourse is an open-source discussion platform. Prior to version 3.1.0.beta3 of the `beta` and `tests-passed` branches, attackers are able to bypass Discourse's server-side request forgery (SSRF) protection for private IPv4 addresses by using a IPv4-mapped IPv6 address. The issue is patched in the latest beta and tests-passed version of Discourse. version 3.1.0.beta3 of the `beta` and `tests-passed` branches. There are no known workarounds.

Category

5.7
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.11%
Vendor Advisory github.com
Affected: discourse discourse
Published at:
Updated at:

References

Link Tags
https://github.com/discourse/discourse/security/advisories/GHSA-26h3-8ww8-v5fc vendor advisory
https://github.com/discourse/discourse/pull/20710 patch
https://github.com/discourse/discourse/commit/fd16eade7fcc6bba4b71e71106a2eb13cdfdae4a patch

Frequently Asked Questions

What is the severity of CVE-2023-28111?
CVE-2023-28111 has been scored as a medium severity vulnerability.
How to fix CVE-2023-28111?
To fix CVE-2023-28111, 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-2023-28111 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2023-28111 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-2023-28111?
CVE-2023-28111 affects discourse discourse.
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