Every CVE Search/ Get API key

CVE-2023-23935

Presence of restricted personal Discourse messages may be leaked if tagged with a tag

3.5 LowFix available

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.

Attack profile

How easy it is to exploit

Attack vector
Network
Complexity
Low
Privileges needed
Low
User interaction
Required

What an attacker can affect

Confidentiality
Low
Integrity
None
Availability
None

Exploit likelihood

0.50%Up 0.5 points since Mar 17, 2023
90%50%10%1%

What each source reports

CVE List Score used 3.5

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.

Record
CVE-2023-23935
CVSS 3.1
3.5 LowCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N
Weakness
CWE-200
Updated
2026-11-02
EUVDEUVD-2023-28006 3.5

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.

Record
EUVD-2023-28006
CVSS 3.1
3.5 LowCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N
Updated
2026-11-02
NVD 3.5

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.

Record
CVE-2023-23935
CVSS 3.1
3.5 LowCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N
CVSS 3.1
4.3 MediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
Weakness
CWE-200
Updated
2026-11-02
OSV 3.5

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.

Record
CVE-2023-23935
CVSS 3.1
3.5 LowCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N
Weakness
CWE-200
Updated
2026-11-02
OSVBIT-discourse-2023-23935 No score

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.

Record
BIT-discourse-2023-23935
Updated
2026-11-02

Affected products

Affected packages

Affected packages
PackageAffectedFixed
discourse
Bitnami
before 3.0.1
3.0.1

History

History
RecordedChangedSources
first indexedCVE List, EUVD, NVD, OSV

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2023-23935 is a low vulnerability (CVSS 3.5) in Discourse, published March 16, 2023. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.50%, the 43rd percentile. Fixed in discourse 3.0.1.

References

MoveEnter Open