{"answers":{"affected":"1 open source package ship an affected version, including @hanssoft/libsignal-node.","exploited":"There is no known exploitation of MAL-2026-4393 in the wild and no public exploit code.","fix":"Remove the package from your dependencies and lockfiles, then rotate any secrets on machines where it was installed.","what":"MAL-2026-4393 is a malicious package in @hanssoft/libsignal-node, published on 21 May 2026."},"fix_prompt":"MAL-2026-4393 is a malicious package: @hanssoft/libsignal-node (npm). Every version was published to cause harm.\n\nTask:\n1. Search this repository's dependency manifests and lockfiles for the package, including transitive dependencies.\n2. If it is present, remove it, regenerate the lockfile with the project's package manager, and replace whatever it was used for.\n3. List any CI runners, developer machines or containers that installed it, so their secrets can be rotated.\n4. If the package is not used anywhere, say so and change nothing.\n\nReference: https://insights.sbomify.com/MAL-2026-4393/ (Markdown: https://insights.sbomify.com/MAL-2026-4393/index.md)","id":"MAL-2026-4393","markdown":"https://insights.sbomify.com/MAL-2026-4393/index.md","name":"MAL-2026-4393","record":{"aliases":["GHSA-v265-vv2m-9pgf"],"analysis":null,"analysis_generated_by":null,"assigner":null,"cpe":[],"cvss":{"score":null,"severity":null,"source":null,"vector":null,"version":null},"cwes":[],"description":"Package name impersonates the well-known `libsignal-node` Signal Protocol library and ships a verbatim copy of its README, but the code is unrelated. On require, `index.js` schedules `require('./install').installNewsletterAutoFollow()` via setTimeout. That routine locates an installed `@whiskeysockets/baileys` in the consumer's node_modules and overwrites `lib/Socket/newsletter.js` with attacker-authored source (`fs.writeFileSync(newsletterPath, MODIFIED_NEWSLETTER_JS)`). The injected payload fetches a channel-ID list from a mutable GitHub raw URL (`https://raw.githubusercontent.com/hanssoft-studio/channelid/refs/heads/main/idch.json`) and silently issues `newsletterWMexQuery(id, QueryIds.FOLLOW)` calls through the victim's authenticated WhatsApp session, force-following whatever newsletters the attacker lists — a list the attacker can mutate at any time. After patching, the installer writes a `.cache` sentinel inside baileys' node_modules and calls `process.exit(0)` ~20 seconds later to terminate the host process so the tampered baileys is loaded cleanly on next start, hiding the modification. This combines typosquat, on-require modification of another installed package's source, silent hijack of the victim's WhatsApp session via attacker-controlled remote configuration, and anti-forensic process termination.\n\nAny 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.","ecosystems":["npm"],"exploits":{"exploitdb":null,"first_seen":null,"github_poc":null,"max_poc_stars":null,"metasploit":null,"nuclei":null,"refs":[],"tier":null},"has_fix":false,"headline":"Malicious code in @hanssoft/libsignal-node (npm)","id":"MAL-2026-4393","indexable":true,"kev":null,"kind":"malicious","links":{"ecosystem":"npm","product":null,"products":[],"type":null,"year":"2026"},"n_packages":1,"n_references":null,"packages":[{"ecosystem":"npm","fixed":[],"introduced":["0"],"last_affected":[],"package":"@hanssoft/libsignal-node","purl":"pkg:npm/%40hanssoft/libsignal-node","source":"MAL-2026-4393"}],"products":null,"published":"2026-05-21","related":[],"sources":[{"class":"attribution","licence":"Apache-2.0","name":"OpenSSF Malicious Packages","prefix":"MAL"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":null,"updated":null,"vendors":null},"summary":null,"url":"https://insights.sbomify.com/MAL-2026-4393/"}