Your RSA-2048 keys break in 2030. Find every one of them before attackers do.
Malicious package

postcss-processor-utilsnpm

postcss-processor-utils is a confirmed malicious npm package (MAL-2026-10540) that steals credentials and exfiltrates sensitive data (malicious versions 1.0.0, 1.0.1, 1.0.2…). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in postcss-processor-utils (npm)

MAL-2026-10540
Immediate action
Remove the package, then rotate any secrets the build/runtime could reach.
npm uninstall postcss-processor-utils

What this malware does

On require, src/index.js loads src/token-loader.js, which reads data/design-tokens.json, XOR-decodes the base64 blobs under _encrypted.chunks using a key derived from the package name and version, writes the decoded JavaScript to os.tmpdir()/postcss-processor-cache/compat-<platform>-<arch>.js, and immediately require()s the result. The XOR-with-package-identity scheme exists only to defeat static scanners; the executed bytes are whatever the publisher chooses to embed. Separately, src/styles.js contains a top-level IIFE (_cssColorProbe) that runs on require, writes process metadata (arch, platform, execPath, pid, timestamp) to /tmp/.tailwind-color-space-v2/, and is gated by !process.env.CI &&!process.env.TAILWIND_DISABLE_TELEMETRY so it only fires on developer machines. The same file (lines 67-74) contains an author comment block reading 'STEALTH PAYLOAD AREA / Replace the example below with your actual virus logic. / This executes once on first build after npm install.' — the author self-identifies the location as a payload slot. The package's exported API mimics @tailwindcss/typography (identical prose plugin, class names, modifiers, selectors) but is published under placeholder identity ('[email protected]', 'github.com/example-org/...'), positioning it as a Tailwind-typography lookalike to lure installs. Any project that installs and requires this package executes attacker-controlled JavaScript on developer (non-CI) hosts.

Any computer that has this package installed or running should be considered fully compromised. All secrets and keys stored on that computer should be rotated immediately from a different computer. The package should be removed, but as full control of the computer may have been given to an outside entity, there is no guarantee that removing the package will remove all malicious software resulting from installing it.

Malicious versions

4 flagged
1.0.01.0.11.0.21.0.3

Indicators of compromise (SHA-256)

b0253c4f750443ba47f0ab61347fa85a1659b847190a85757575e904966636da
964d32bf7c4b15509607e1e7bce59d3c5a06ecf914bc1035f778163b0fe16e95
445efe5179752269d6f76332cbc7db12f17f8fd158295a154fe46e3175dba3d2
9f4dfce5e5320af545bf33c38838efe48a05c80e18af98b5d9656d3d9a560290
f8ee90472e41f6dadcecfbc4caa2e85c67686d98633b928b45eafbc469a756a5

Detection & response playbook

Credential / info stealer
  1. Find it

    Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for postcss-processor-utils (4 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging postcss-processor-utils across your stack and pipelines.

  2. If you installed it — respond

    postcss-processor-utils is built to steal secrets, so assume every credential the build or runtime could read is compromised. Remove it from your project and lockfile, then rotate ALL exposed secrets — npm/registry tokens, cloud keys, CI/CD secrets, SSH keys, and any .env values — from a known-clean machine. Audit logs for unauthorized use of those credentials.

  3. Did it already run?

    If postcss-processor-utils was ever installed, its post-install/runtime payload may have already executed. O3's L7 egress monitoring and runtime eBPF sensors detect the credential exfiltration or command-and-control callback after install and block the malicious outbound channel, so you catch and contain the actual compromise — not just the presence of the package.

  4. How O3 protects you

    O3 blocks postcss-processor-utils before install through its supply-chain scanner, and if it has already run, detects and severs the exfiltration or C2 callback at runtime through L7 egress monitoring and eBPF.

Frequently asked questions

No. postcss-processor-utils on npm has been identified as a malicious package (versions 1.0.0, 1.0.1, 1.0.2, 1.0.3 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-010375GHSA-r5fg-j5cf-mfgxIN-MAL-2026-010639IN-MAL-2026-010643IN-MAL-2026-010644

References

Credits

  • Amazon Inspector · finder

Detect & block this

O3 blocks postcss-processor-utils-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.

Explore

postcss-processor-utils (npm) malicious package — MAL-2026-10540 | O3 Security