CVE-2025-59140 [email protected] contains malware after npm account takeover
Attackers injected malware into an npm package to hijack cryptocurrency transactions in browser environments, requiring users to upgrade and rebuild bundles.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-59140?
CVE-2025-59140 is a high-severity vulnerability in Qix- node-backslash, published on 15 Sep 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
backlash parses collected strings with escapes. On 8 September 2025, the npm publishing account for backslash was taken over after a phishing attack. Version 0.2.1 was published, functionally identical to the previous patch version, but with a malware payload added attempting to redirect cryptocurrency transactions to the attacker's own addresses from within browser environments. Local environments, server environments, command line applications, etc. are not affected. If the package was used in a browser context (e.g. a direct <script> inclusion, or via a bundling tool such as Babel, Rollup, Vite, Next.js, etc.) there is a chance the malware still exists and such bundles will need to be rebuilt. The malware seemingly only targets cryptocurrency transactions and wallets such as MetaMask. npm removed the offending package from the registry over the course of the day on 8 September, preventing further downloads from npm proper. On 13 September, the package owner published new patch versions to help cache-bust those using private registries who might still have the compromised version cached. Users should upgrade to the latest patch version, completely remove their node_modules directory, clean their package manager's global cache, and rebuild any browser bundles from scratch. Those operating private registries or registry mirrors should purge the offending versions from any caches. This issues is resolved in 0.2.2.
Weakness: CWE-506
Which versions are affected by CVE-2025-59140?
How do I fix CVE-2025-59140?
Upgrade to a fixed version.
Is CVE-2025-59140 being exploited?
There is no known exploitation of CVE-2025-59140 in the wild and no public exploit code.