CVE-2022-39236: Matrix Javascript SDK is the Matrix Client-Server SDK for JavaScript.

Matrix Javascript SDK is the Matrix Client-Server SDK for JavaScript.

Matrix Javascript SDK is the Matrix Client-Server SDK for JavaScript. Starting with version 17.1.0-rc.1, improperly formed beacon events can disrupt or impede the matrix-js-sdk from functioning properly, potentially impacting the consumer's ability to process data safely. Note that the matrix-js-sdk can appear to be operating normally but be excluding or corrupting runtime data presented to the consumer. This is patched in matrix-js-sdk v19.7.0. Redacting applicable events, waiting for the sync processor to store data, and restarting the client are possible workarounds. Alternatively, redacting the applicable events and clearing all storage will fix the further perceived issues. Downgrading to an unaffected version, noting that such a version may be subject to other vulnerabilities, will additionally resolve the issue.

Description from the National Vulnerability Database, published by GitHub

What it means for a small business

If your business uses matrix-js-sdk, install the vendor's update. If you're not sure whether you use it, ask whoever manages your computers.

How likely is an attack? The Exploit Prediction Scoring System, run by FIRST (the global association of security response teams), puts the odds of this one being exploited in the next 30 days at 1.4%, higher than 71% of CVEs. That’s above average: worth scheduling this week. Scored October 28, 2026, updated daily.

Check your own setup

Website check: reads what your site runs from the outside (WordPress version, plugins it can see, old server software) and matches it against this database.
Server check: what your web server says about itself, and whether that version has known flaws.

Sources

Part of the Huttenlocher Technologies vulnerability database, refreshed twice a day from CISA and the NVD. The title, category and plain-language guidance are ours; check the linked record before acting on a detail. This is general guidance, not a review of your systems.

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