Summary
matrix-js-sdk Prototype Pollution vulnerability
Workarounds
Redacting applicable events, waiting for the sync processor to store data, and restarting the client can often fix it. Alternatively, redacting the applicable events and clearing all storage will often fix most perceived issues.
In some cases, no workarounds are possible.
References
https://learn.snyk.io/lessons/prototype-pollution/javascript/
For more information
If you have any questions or comments about this advisory please email us at security at matrix.org.
Impact
Events sent with special strings in key places can temporarily 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.
CVE-2022-36059 has a CVSS score of 7.2 (High). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (19.4.0); upgrading removes the vulnerable code path.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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This is fixed in matrix-js-sdk 19.4.0.
Frequently Asked Questions
- What is CVE-2022-36059? CVE-2022-36059 is a high-severity security vulnerability in matrix-js-sdk (npm), affecting versions < 19.4.0. It is fixed in 19.4.0.
- How severe is CVE-2022-36059? CVE-2022-36059 has a CVSS score of 7.2 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Which versions of matrix-js-sdk are affected by CVE-2022-36059? matrix-js-sdk (npm) versions < 19.4.0 is affected.
- Is there a fix for CVE-2022-36059? Yes. CVE-2022-36059 is fixed in 19.4.0. Upgrade to this version or later.
- Is CVE-2022-36059 exploitable, and should I be worried? Whether CVE-2022-36059 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2022-36059 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2022-36059? Upgrade
matrix-js-sdkto 19.4.0 or later.