Presence of restricted personal Discourse messages may be leaked if tagged with a tag
Discourse is an open-source messaging platform. In versions 3.0.1 and prior on the `stable` branch and versions 3.1.0.beta2 and prior on the `beta` and `tests-passed` branches, the count of personal messages displayed for a tag is a count of all personal messages regardless of whether the personal message is visible to a given user. As a result, any users can technically poll a sensitive tag to determine if a new personal message is created even if the user does not have access to the personal message. In the patched versions, the count of personal messages tagged with a given tag is hidden by default. To revert to the old behaviour of displaying the count of personal messages for a given tag, an admin may enable the `display_personal_messages_tag_counts` site setting.
- Published
- Mar 16, 2023
- Updated
- Jun 17, 2026
- EPSS
- 0.5% · 41th percentile
- CWE
- CWE-200
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Report tools
Action score
17
Monitor
Low priority for now.
- CVSS
- 17 / 40 · 4.3 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.5%
CISA SSVC decision
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- 4.3
- CNA · GitHub_M
- 3.5
- 0.8 point gap
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Noroxi analysis
No Noroxi analysis for this record yet
We don't hand-write analysis for the hundreds of thousands of vulnerabilities in the database; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.
We use this product, ask for helpAffected systems
| Vendor | Product | CPE |
|---|---|---|
| discourse | discourse | cpe:2.3:a:discourse:discourse |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- discourse discoursebefore 3.0.1
- discourse discourse1.1.0
- discourse discourse1.2.0
- discourse discourse1.3.0
- discourse discourse1.4.0
- discourse discourse1.5.0
- discourse discourse1.6.0
- discourse discourse1.7.0
- discourse discourse1.8.0
- discourse discourse1.9.0
- discourse discourse2.0.0
- discourse discourse2.1.0
- discourse discourse2.2.0
- discourse discourse2.3.0
- discourse discourse2.4.0
- discourse discourse2.5.0
- discourse discourse2.6.0
- discourse discourse2.7.0
- discourse discourse2.8.0
- discourse discourse2.9.0
Versions reported by the vendor
Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.
discourse discourse
- stable <= 3.0.1, beta <= 3.1.0.beta2, tests-passed <= 3.1.0.beta2affected
Same product
discourse: all recordsOther highest-scoring records for the same primary product.
- CVE-2021-41163RCE via malicious SNS subscription payload45Plan
- CVE-2025-68662FinalDestination hostname matching allows SSRF protection bypass39Monitor
- CVE-2023-47121Discourse SSRF vulnerability in Embedding39Monitor
- CVE-2026-55674Discourse: Cache poisoning/XSS via color scheme cookies37Monitor
- CVE-2026-53963Discourse: Stored-XSS in 2FA delete confirmation modal36Monitor
- CVE-2024-49765Bypass of Discourse Connect using other login paths if enabled in Discourse36Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
No fix version is recorded for this entry. Check the references for vendor advisories.
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
The product’s vendor appears in a public program. Matched by name; verify the scope text in the program.
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- A low-privileged account is enough.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- low · data can be read
- Integrity
- none
- Availability
- none
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- Low
- Integrity impact
- None
- Availability impact
- None
Weakness class (CWE)
CWE-200 · Exposure of Sensitive Information to an Unauthorized ActorCVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
nvd-primary
Root cause
The extension requests broader permissions than its function needs and sends the data it collects out for purposes beyond its stated function.
The bug in code
The whole CWE-200 classA representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.
Vulnerable
{ "permissions": ["tabs", "<all_urls>"], "background": { "service_worker": "analytics.js" }}Fixed
{ "permissions": ["activeTab"], "host_permissions": ["https://yildiz.example/*"]}Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
- ExcavationCAPEC-116likelihood: High · Medium
- Subverting Environment Variable ValuesCAPEC-13likelihood: High · Very High
- FootprintingCAPEC-169likelihood: High · Very Low
- Exploiting Trust in ClientCAPEC-22likelihood: High · High
- FingerprintingCAPEC-224likelihood: High · Very Low
- ICMP Echo Request PingCAPEC-285likelihood: Medium · Low
- TCP SYN ScanCAPEC-287Low
- Enumerate Mail Exchange (MX) RecordsCAPEC-290Low
ATT&CK techniques
- System Service DiscoveryT1007
- System Network Configuration DiscoveryT1016
- Remote System DiscoveryT1018
- System Owner/User DiscoveryT1033
- Masquerading: Match Legitimate Name or LocationT1036.005
- Network Service ScanningT1046
- System Network Connections DiscoveryT1049
- Process DiscoveryT1057
- Permission Groups DiscoveryT1069
- System Information DiscoveryT1082
- File and Directory DiscoveryT1083
- Account DiscoveryT1087
- Multi-Factor Authentication InterceptionT1111
- Peripheral Device DiscoveryT1120
- System Time DiscoveryT1124
- Access Token Manipulation:Token Impersonation/TheftT1134.001
Change log
No changes recorded on tracked fields yet. Score, KEV, exploit maturity and fix status changes appear here.
References
- github.com/discourse/discourse/commit/f31f0b70f82c43d93220ce6fc0d4f57440452f37
- github.com/discourse/discourse/security/advisories/GHSA-rf8j-mf8c-82v7
Vendor advisories and official records. Exploit/PoC links are deliberately left out.