How severe is GHSA-c9vx-2g7w-rp65?

GHSA-c9vx-2g7w-rp65 has a CVSS score of 6.1/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by GHSA-c9vx-2g7w-rp65?

GHSA-c9vx-2g7w-rp65 affects the following packages: matrix-react-sdk (npm). Ecosystems affected: npm.

How do I fix GHSA-c9vx-2g7w-rp65?

Update matrix-react-sdk to 3.76.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-c9vx-2g7w-rp65 is resolved across your whole dependency graph.

How do I detect GHSA-c9vx-2g7w-rp65 in my npm dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for matrix-react-sdk, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate GHSA-c9vx-2g7w-rp65 if there is no patch (or I can't update yet)?

Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.

Is GHSA-c9vx-2g7w-rp65 actively exploited in the wild?

No public exploit code has been indexed for GHSA-c9vx-2g7w-rp65 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-c9vx-2g7w-rp65?

GHSA-c9vx-2g7w-rp65 has an EPSS (Exploit Prediction Scoring System) score of 0.5%, placing it in the 39th 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-c9vx-2g7w-rp65?

GHSA-c9vx-2g7w-rp65 is classified as Cross-site Scripting (XSS) (CWE-79). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

When was GHSA-c9vx-2g7w-rp65 published, and has it been updated?

GHSA-c9vx-2g7w-rp65 was published on July 18, 2023 and was last updated on November 8, 2023. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

📦

📦 npm

Not in CISA KEV

MEDIUM severity

matrix-react-sdk vulnerable to XSS in Export Chat featureGHSA-c9vx-2g7w-rp65

MEDIUMFix: matrix-org/matrix-react-sdk@22fcd34

GHSA-c9vx-2g7w-rp65 is a medium-severity (CVSS 6.1) Cross-site Scripting (XSS) vulnerability in matrix-react-sdk. A fix is available for matrix-react-sdk — see the affected versions and patch details below.

Also known asCVE-2023-37259

Published

Jul 18, 2023

Updated

Nov 8, 2023

Affected

1 pkg

Patched

1 / 1

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-c9vx-2g7w-rp65.

EPSS Exploitation Probability

via FIRST.org ↗

0.5%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs39th percentile — riskier than 39% 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

1 pkg affected

How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.

3other npm packages depend on this — each one inherits the vulnerability until it's patched upstream

matrix-react-sdknpm

9Kdownloads / week

Description

matrix-react-sdk is a react-based SDK for inserting a Matrix chat/voip client into a web page. The Export Chat feature includes certain attacker-controlled elements in the generated document without sufficient escaping, leading to stored Cross site scripting (XSS). Since the Export Chat feature generates a separate document, an attacker can only inject code run from the null origin, restricting the impact. However, the attacker can still potentially use the XSS to leak message contents. A malicious homeserver is a potential attacker since the affected inputs are controllable server-side. This issue has been addressed in commit 22fcd34c60 which is included in release version 3.76.0. Users are advised to upgrade. The only known workaround for this issue is to disable or to not use the Export Chat feature.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
📦npm	`matrix-react-sdk`	≥ 3.32.0&&< 3.76.0	3.76.0`npm install matrix-react-sdk@3.76.0`

Affected Products

1 product · 3 configurations

Application

matrix-react-sdkmatrix-react-sdk_project

≥ 3.32.0 && < 3.76.0

1 version

3.76.0

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for matrix-react-sdk, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update matrix-react-sdk to 3.76.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-c9vx-2g7w-rp65 is resolved across your whole dependency graph.
Workarounds
Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.

Frequently Asked Questions

### Description The Export Chat feature includes certain attacker-controlled elements in the generated document without sufficient escaping, leading to stored XSS. ### Impact Since the Export Chat feature generates a separate document, an attacker can only inject code run from the `null` origin, restricting the impact. However, the attacker can still potentially use the XSS to leak message contents. A malicious homeserver is a potential attacker since the affected inputs are controllable server-side. ### Patches This was patched in matrix-react-sdk 3.76.0. ### Workarounds None, other tha