chai-jsonss (npm) · Malicious Code
Affects chai-jsonssSource GCVE Database
Malicious package : remove chai-jsonss and rotate any secrets on hosts that installed it.
Data as of 10 Aug 2026, 15:57 UTC
Malicious package
Published to npm · OSV MAL-2026-13692
What to do
Remove chai-jsonss from every project, lockfile and image that pulls it in. Treat any host that installed it as compromised: rotate the credentials, tokens and keys it could read, from a clean machine.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| npmchai-jsonss | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
Description
The npm package chai-jsonss version 3.7.7 contains malicious code that executes attacker-controlled JavaScript during import. It fetches a base64-encoded payload from a remote URL, decodes it, and executes it in-process using new Function, enabling remote code execution. The package masquerades as related to chai but has no chai functionality. This behavior occurs immediately on import without user interaction.