CVE-2023-28112

Discourse's SSRF protection missing for some FastImage requests

HIGH
8.1
CVSS Score
Published: March 17, 2023 at 06:35 PM UTC
Updated: June 17, 2026 at 05:46 AM UTC
1 product affected across 1 vendorDiscourse

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Severity
HIGH8.1
Exploit prediction
EPSS 0.6%
SSVC
No known exploit

Description

Discourse is an open-source discussion platform. Prior to version 3.1.0.beta3 of the `beta` and `tests-passed` branches, some user provided URLs were being passed to FastImage without SSRF protection. Insufficient protections could enable attackers to trigger outbound network connections from the Discourse server to private IP addresses. This affects any site running the `tests-passed` or `beta` branches versions 3.1.0.beta2 and prior. This issue is patched in version 3.1.0.beta3 of the `beta` and `tests-passed` branches. There are no known workarounds.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v ≤ 3.1.0v < 3.1.0v < 3.1.0.beta33.1.0 beta13.1.0 beta2
Affected range stops below 3.1.0, so it looks safe — our inference, not a vendor statement
Affected range stops below 3.1.0.beta3, so it looks safe — our inference, not a vendor statement

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
NONE
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-918

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