High

matrix-js-sdk Prototype Pollution vulnerability

  • Disclosed: 28.03.2023
  • Updated: 11.10.2026 10:22

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.

Patches

This is fixed in matrix-js-sdk 19.4.0.

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.

Affected software

Click a technology to see all vulnerabilities affecting it.

PlatformPackageVulnerable versionsFixed in
npm package matrix-js-sdk < 19.4.0 19.4.0

References

CVSS score 7.2/10
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
Weakness (CWE)
CWE-1321
Platform
npm
Package
matrix-js-sdk
Disclosed
28.03.2023
Updated
11.10.2026 10:22

Sources and licenses

OSV / GitHub Advisory Database - GHSA-rfv9-x7hh-xc32 - CC BY 4.0

Vulnerability history: matrix-js-sdk

All published vulnerabilities of this package (npm package), newest first. Shows whether this is a one-off slip or a package that needs watching.

All (12) in the archive
Total entries
12
First → latest
09.2021 09.2025
Without a fix
0
Exploited in attacks
0

Severity breakdown

  • High 6
  • Medium 6

Disclosures per year

  1. 2021: 1
  2. 2022: 4
  3. 2023: 3
  4. 2024: 3
  5. 2025: 1
  6. 2026: 0
Severity:
  1. High · 8.2 CVE-2023-28427 < 24.0.0 24.0.0
  2. matrix-js-sdk Prototype Pollution vulnerability this entry
    High · 7.2 CVE-2022-36059 < 19.4.0 19.4.0

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