How severe is GHSA-44mv-jq72-gj49?

GHSA-44mv-jq72-gj49 has a CVSS score of 4.3/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by GHSA-44mv-jq72-gj49?

GHSA-44mv-jq72-gj49 affects the following packages: github.com/mattermost/mattermost/server/v8 (Go), github.com/mattermost/mattermost-server (Go), github.com/mattermost/mattermost-server (Go), github.com/mattermost/mattermost-server (Go), github.com/mattermost/mattermost-server (Go). Ecosystems affected: Go.

How do I fix GHSA-44mv-jq72-gj49?

Update github.com/mattermost/mattermost/server/v8 to 8.0.0-20260115183946-38b413a27604 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-44mv-jq72-gj49 is resolved across your whole dependency graph.

How do I detect GHSA-44mv-jq72-gj49 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 GHSA-44mv-jq72-gj49 if there is no patch (or I can't update yet)?

Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.

Is GHSA-44mv-jq72-gj49 actively exploited in the wild?

No public exploit code has been indexed for GHSA-44mv-jq72-gj49 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 GHSA-44mv-jq72-gj49?

GHSA-44mv-jq72-gj49 has an EPSS (Exploit Prediction Scoring System) score of 0.2%, placing it in the 14th 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 GHSA-44mv-jq72-gj49?

GHSA-44mv-jq72-gj49 is classified as CWE-789 (CWE-789). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was GHSA-44mv-jq72-gj49 published, and has it been updated?

GHSA-44mv-jq72-gj49 was published on March 16, 2026 and was last updated on April 27, 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

MEDIUM severity

Mattermost fails to bound memory allocation when processing PSD image filesGHSA-44mv-jq72-gj49

MEDIUMFix: mattermost/mattermost@38b413a

GHSA-44mv-jq72-gj49 is a medium-severity (CVSS 4.3) CWE-789 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.

Also known asCVE-2026-26246GO-2026-4727

Published

Mar 16, 2026

Updated

Apr 27, 2026

Affected

5 pkgs

Patched

5 / 5

Exploits

None indexed

Exploitation data as of Nov 3, 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 GHSA-44mv-jq72-gj49.

EPSS Exploitation Probability

via FIRST.org ↗

0.2%probability of exploitation in next 30 days

Lower Risk+0.01%

Lower risk than most CVEs14th percentile — riskier than 14% 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

5 pkgs affected

🐹github.com/mattermost/mattermost/server/v8🐹github.com/mattermost/mattermost-server🐹github.com/mattermost/mattermost-server🐹github.com/mattermost/mattermost-server🐹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 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to bound memory allocation when processing PSD image files which allows an authenticated attacker to cause server memory exhaustion and denial of service via uploading a specially crafted PSD file. Mattermost Advisory ID: MMSA-2026-00572

Affected Packages

5 total 5 fixed

Ecosystem	Package	Vulnerable range	Fix
🐹Go	`github.com/mattermost/mattermost/server/v8`	all versions	8.0.0-20260115183946-38b413a27604`go get github.com/mattermost/mattermost/server/v8@v8.0.0-20260115183946-38b413a27604`
🐹Go	`github.com/mattermost/mattermost-server`	all versions	5.3.2-0.20260115183946-38b413a27604`go get github.com/mattermost/mattermost-server@v5.3.2-0.20260115183946-38b413a27604`
🐹Go	`github.com/mattermost/mattermost-server`	≥ 10.11.0-rc1&&< 10.11.11	10.11.11`go get github.com/mattermost/mattermost-server@v10.11.11`
🐹Go	`github.com/mattermost/mattermost-server`	≥ 11.2.0-rc1&&< 11.2.3	11.2.3`go get github.com/mattermost/mattermost-server@v11.2.3`
🐹Go	`github.com/mattermost/mattermost-server`	≥ 11.3.0-rc1&&< 11.3.1	11.3.1`go get github.com/mattermost/mattermost-server@v11.3.1`

Affected Products

1 product · 3 configurations

Application

mattermost servermattermost

≥ 11.3.0 && < 11.3.1

range

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 8.0.0-20260115183946-38b413a27604 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-44mv-jq72-gj49 is resolved across your whole dependency graph.
Workarounds
Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.

Frequently Asked Questions

O3 Security · Impact-Aware SCA

Is GHSA-44mv-jq72-gj49 in your dependencies?

Find it across Go, including transitive dependencies.

Scan my dependencies How O3 SCA works

CVSS Score

4.3/10CVSS v3 base

Vector breakdown

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

Low

Raw vector

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

CWE Classification

CWE-789CWE-789

Weaponization

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

OpenSSF Scorecard

Package health score

mattermost

7.3/10

Maintained10/10

Dependency-Update-Tool10/10

Code-Review10/10

Branch-Protection4/10

Vulnerabilities0/10

Assessed Nov 2, 2026

Timeline

Disclosed

Mar 16, 2026

Last updated

Apr 27, 2026

Identifiers

GHSA-44mv-jq72-gj49

GO-2026-4727

References

Advisorynvd.nist.gov · CVE 2026 26246 Webgithub.com · 38b413a27604e8721fbe008f8ec4b4e6c47ad4f0 Webmattermost.com · security updates Packagegithub.com · mattermost

Related vulnerabilities

This CVE is medium severity; 7 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 verifiedApr 27, 2026

Mattermost fails to bound memory allocation when processing PSD image filesGHSA-44mv-jq72-gj49

Exploitation Status

No confirmed exploitation observed yet

EPSS Exploitation Probability

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

Description

Affected Packages

Affected Products

Detection & mitigation playbook

Detect

Fix

Workarounds

Frequently Asked Questions

Is GHSA-44mv-jq72-gj49 in your dependencies?