Which versions of @solana-js/web3 are malicious?

The following npm versions of @solana-js/web3 are flagged malicious: 1.91.3. Treat any of these as compromised.

How do I remediate @solana-js/web3 if I installed it?

@solana-js/web3 is a typosquat — you almost certainly intended a legitimately-named package. Remove @solana-js/web3, install the correct package, and rotate any secrets exposed during the install since post-install scripts may have already run.

I already installed @solana-js/web3 — how do I know if it already compromised me?

If @solana-js/web3 was installed, its post-install payload may already have run. Removing the package does not undo that — check outbound connections and credential use from the install window onward.

Is @solana-js/web3 part of a known attack campaign?

Yes — @solana-js/web3 is associated with the IN-MAL-2026-017665 campaign. Packages in the same campaign often share infrastructure and payloads, so check whether any related packages are also in your dependency tree.

How do I find @solana-js/web3 across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for @solana-js/web3 (version 1.91.3).

Malicious package

@solana-js/web3npm

Advisory published Aug 13, 2026Updated Aug 13, 2026

@solana-js/web3 is a confirmed malicious npm package (MAL-2026-13941) that typosquats a legitimate package to trick installs (malicious version 1.91.3). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in @solana-js/web3 (npm)

MAL-2026-13941

Immediate action

Remove the package, then rotate any secrets the build/runtime could reach.

npm uninstall @solana-js/web3

What this malware does

Package name @solana-js/web3 impersonates the legitimate @solana/web3.js SDK, and package.json falsely attributes authorship to 'Solana Labs' with a solana.com homepage. The exported API is a non-functional stub (Connection.getBalance returns 0, sendTransaction returns random bytes) — no real Solana client functionality is present. On install, scripts/postinstall.js detects Windows and spawns a hidden PowerShell (-NoP -W Hidden -Exec Bypass) with a base64-encoded command. The decoded PowerShell performs an AMSI bypass via reflection over System.Management.Automation.AmsiUtils, downloads a binary payload from https://files.catbox.moe/a3loxy.bin, and executes it in-process using VirtualAlloc/CreateThread. The postinstall script further hex-escapes API names ('child_process', 'powershell', 'platform', 'win32') and fragments the PowerShell payload to hinder review. The result is arbitrary remote code execution on any Windows host that runs npm install against this package, with the shellcode fetched from an anonymous, mutable file host (files.catbox.moe) — a known-bad-infrastructure dropper pattern.

Malicious versions

1 flagged

1.91.3

Indicators of compromise (SHA-256)

9b539591552f3e960f65ceb70d946bc56f240f9bdb1400c501723aa32fd305ec

Detection & response playbook

Typosquat

Find it
Search your lockfiles and build artifacts for @solana-js/web3 (version 1.91.3).
If you installed it — respond
@solana-js/web3 is a typosquat — you almost certainly intended a legitimately-named package. Remove @solana-js/web3, install the correct package, and rotate any secrets exposed during the install since post-install scripts may have already run.
Did it already run?
If @solana-js/web3 was installed, its post-install payload may already have run. Removing the package does not undo that — check outbound connections and credential use from the install window onward.

Frequently asked questions

No. @solana-js/web3 on npm has been identified as a malicious package (version 1.91.3 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-017665

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks @solana-js/web3-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the malicious outbound activity and severs the channel.

Malware detection Runtime egress monitoring

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