How severe is CVE-2024-39837?

CVE-2024-39837 has a CVSS score of 3.8/10, rated LOW. Review your exposure and patch according to your risk tolerance.

Which packages are affected by CVE-2024-39837?

CVE-2024-39837 affects the following packages: github.com/mattermost/mattermost/server/v8 (Go), github.com/mattermost/mattermost/server/v8 (Go), github.com/mattermost/mattermost/server/v8 (Go), github.com/mattermost/mattermost-server (Go), github.com/mattermost/mattermost-server/v5 (Go), github.com/mattermost/mattermost-server/v6 (Go), github.com/mattermost/mattermost-server (Go). Ecosystems affected: Go.

How do I fix CVE-2024-39837?

Update github.com/mattermost/mattermost/server/v8 to 9.5.7 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-39837 is resolved across your whole dependency graph.

How do I detect CVE-2024-39837 in my Go dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/mattermost/mattermost/server/v8, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2024-39837 if there is no patch (or I can't update yet)?

Put an independent control in front of the weakness: restrict the affected endpoint or interface to trusted networks, require an additional authentication factor or proxy-level check, and invalidate existing sessions and credentials in case the flaw has already been used.

Is CVE-2024-39837 actively exploited in the wild?

No public exploit code has been indexed for CVE-2024-39837 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2024-39837?

CVE-2024-39837 has an EPSS (Exploit Prediction Scoring System) score of 0.3%, placing it in the 21th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2024-39837?

CVE-2024-39837 is classified as CWE-284 (CWE-284). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2024-39837 published, and has it been updated?

CVE-2024-39837 was published on August 1, 2024 and was last updated on October 28, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐹

🐹 Go

Not in CISA KEV

LOW severity

CVE-2024-39837 — server

LOW

CVE-2024-39837 is a low-severity (CVSS 3.8) CWE-284 vulnerability in github.com/mattermost/mattermost/server/v8. A fix is available for github.com/mattermost/mattermost/server/v8 — see the affected versions and patch details below.

Malicious remote can create arbitrary channels

Also known asBIT-mattermost-2024-39837GHSA-vvpg-55p7-5h8wGO-2024-3032

Published

Aug 1, 2024

Updated

Oct 28, 2026

Affected

7 pkgs

Patched

7 / 7

Exploits

None indexed

Exploitation data as of Nov 6, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for CVE-2024-39837.

EPSS Exploitation Probability

via FIRST.org ↗

0.3%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs21th percentile — riskier than 21% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

7 pkgs affected

🐹github.com/mattermost/mattermost/server/v8🐹github.com/mattermost/mattermost/server/v8🐹github.com/mattermost/mattermost/server/v8🐹github.com/mattermost/mattermost-server🐹github.com/mattermost/mattermost-server/v5🐹github.com/mattermost/mattermost-server/v6🐹github.com/mattermost/mattermost-server

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.

Description

Mattermost versions 9.9.x <= 9.9.0, 9.5.x <= 9.5.6 fail to properly restrict channel creation which allows a malicious remote to create arbitrary channels, when shared channels were enabled.

Affected Packages

7 total 7 fixed

Ecosystem	Package	Vulnerable range	Fix
🐹Go	`github.com/mattermost/mattermost/server/v8`	≥ 9.5.0&&< 9.5.7	9.5.7`go get github.com/mattermost/mattermost/server/v8@v9.5.7`
🐹Go	`github.com/mattermost/mattermost/server/v8`	≥ 9.9.0&&< 9.9.1	9.9.1`go get github.com/mattermost/mattermost/server/v8@v9.9.1`
🐹Go	`github.com/mattermost/mattermost/server/v8`	all versions	8.0.0-20240626164322-c758cecaf30c`go get github.com/mattermost/mattermost/server/v8@v8.0.0-20240626164322-c758cecaf30c`
🐹Go	`github.com/mattermost/mattermost-server`	≥ 9.9.0&&< 9.9.1	9.9.1`go get github.com/mattermost/mattermost-server@v9.9.1`
🐹Go	`github.com/mattermost/mattermost-server/v5`	all versions	5.3.2-0.20240626164322-c758cecaf30c`go get github.com/mattermost/mattermost-server/v5@v5.3.2-0.20240626164322-c758cecaf30c`
🐹Go	`github.com/mattermost/mattermost-server/v6`	all versions	6.0.0-20240626164322-c758cecaf30c`go get github.com/mattermost/mattermost-server/v6@v6.0.0-20240626164322-c758cecaf30c`

Affected Products

1 product · 2 configurations

Application

mattermost servermattermost

≥ 9.5.0 && < 9.5.7

1 version

9.9.0

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/mattermost/mattermost/server/v8, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/mattermost/mattermost/server/v8 to 9.5.7 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-39837 is resolved across your whole dependency graph.
Workarounds
Put an independent control in front of the weakness: restrict the affected endpoint or interface to trusted networks, require an additional authentication factor or proxy-level check, and invalidate existing sessions and credentials in case the flaw has already been used.

Frequently Asked Questions

Mattermost versions 9.9.x <= 9.9.0, 9.5.x <= 9.5.6 fail to properly restrict channel creation which allows a malicious remote to create arbitrary channels, when shared channels were enabled.

O3 Security · Impact-Aware SCA

Is CVE-2024-39837 in your dependencies?

Find it across Go, including transitive dependencies.

Scan my dependencies How O3 SCA works

CVSS Score

3.8/10CVSS v3 base

Vector breakdown

Attack Vector

Network

Attack Complexity

Low

Privileges Required

High

User Interaction

None

Scope

Unchanged

Confidentiality

Low

Integrity

Low

Availability

None

Raw vector

CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:N

CWE Classification

CWE-284CWE-284

Weaponization

No Nuclei template, Metasploit module or public proof-of-concept found.

Timeline

Disclosed

Aug 1, 2024

Last updated

Oct 28, 2026

Identifiers

CVE-2024-39837

GHSA-vvpg-55p7-5h8w

BIT-mattermost-2024-39837

GO-2024-3032

References

Advisorygithub.com · CVE 2024 39837.json Advisorynvd.nist.gov · CVE 2024 39837 Webmattermost.com · security updates Webpkg.go.dev · GO 2024 3032 Packagegithub.com · mattermost

Related vulnerabilities

This CVE is low severity; 8 of 8 other CVEs affecting v8 are rated as high or higher (top: high).

CVE-2026-8823CVE-2026-6046CVE-2026-7387CVE-2026-6961CVE-2026-7184CVE-2026-6689CVE-2026-6739CVE-2026-3433

Provenance

Sources

OSV.devNVDFIRST.org (EPSS)

Last verifiedOct 28, 2026