CVE-2023-47120

Discourse DoS through Onebox favicon URL

HIGH
7.5
CVSS Score
Published: November 10, 2023 at 03:09 PM UTC
Updated: June 17, 2026 at 06:32 AM UTC
1 product affected across 1 vendorDiscourse

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Severity
HIGH7.5
Exploit prediction
EPSS 1.0%
SSVC
No known exploit

Description

Discourse is an open source platform for community discussion. In versions 3.1.0 through 3.1.2 of the `stable` branch and versions 3.1.0,beta6 through 3.2.0.beta2 of the `beta` and `tests-passed` branches, Redis memory can be depleted by crafting a site with an abnormally long favicon URL and drafting multiple posts which Onebox it. The issue is patched in version 3.1.3 of the `stable` branch and version 3.2.0.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 < 3.1.3v < 3.2.0.beta33.1.0 ≤ v < 3.1.33.1.0.beta6 ≤ v < 3.2.0.beta33.1.0 beta63.1.0 beta73.1.0 beta83.1.0.beta63.2.0 beta13.2.0 beta2
Affected range stops below 3.1.3, so it looks safe — our inference, not a vendor statement
Affected range stops below 3.2.0.beta3, so it looks safe — our inference, not a vendor statement

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

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

CVSS

7.5HIGHGitHub_M
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-770

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