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🛡️ MAL-2026-5189 — arjson

⚪ Unknown ✅ No Known Exploit OSV
N/A
CVSS Score
0 Low4 Medium7 High9 Critical10

Description

Malicious code in arjson (npm)

Source: amazon-inspector

package.json declares "preinstall": "./.github/scripts/precheck", which on npm install executes a 976KB UPX-packed Linux ELF binary shipped under .github/scripts/ (a path designed to look like CI tooling). The binary has no accompanying source, is compressed with UPX (http://upx.sf.net banner present in the packed image) to defeat static inspection, and its embedded strings reveal capabilities far beyond anything a JSON serialization library would require: libbpf/eBPF (LIBBPF_0.0), kernel tracing (PTRACE), netlink socket-diag enumeration (NETLINK_*_DIAG, INODE), HTTP client primitives (HTTP/1.1, POST, DELETE), GitHub API client (2022-11-28), Windows path handling (USERPROFILE), and asymmetric crypto (Ed25519, MLKEM, RSA_PKCS1_). Any developer or CI system running npm install arjson on Linux will execute opaque packed native code with kernel-level introspection and HTTP-exfiltration capability. The package is advertised as a JSON library; no legitimate purpose exists for shipping a packed eBPF/HTTP-capable preinstall binary.

Source: google-open-source-security

This package was compromised as part of the IronWorm campaign. This campaign executes a malicious binary payload during installation via a preinstall hook. The payload is a Rust-built infostealer that targets developer environments, scanning for and harvesting credentials related to cloud providers, object storage, databases, source-control, package registries, and AI developer tools. It also targets cryptocurrency wallets, specifically injecting a malicious JavaScript hook into the Exodus desktop wallet to capture passwords and recovery phrases. Furthermore, the malware exhibits worm-like behavior by stealing GitHub and NPM credentials to push malicious updates to the victim's repositories and publish trojanized packages, and it uses an eBPF-based kernel rootkit to hide its processes and network connections on Linux systems.

Affected software

MAL-2026-5189 is recorded against 1 package.

  • arjson

Timeline and source

Published on 4 June 2026 and last revised on 12 June 2026. No public exploit is currently recorded for this entry. Record sourced from OSV.

References

www.ox.security (Article)
research.jfrog.com (Article)
www.npmjs.com (Package)

Details

Severity Unknown
CVSS Score N/A
CVSS Vector N/A
CWE N/A
Public Exploit ✅ No
Source OSV
Published 2026-06-04
Updated 2026-08-20
Modified 2026-06-12
Fix URL N/A

Affected Packages

Software From version Fixed in
arjson — —

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ⓘ Data Notice: The information presented above has been compiled from publicly available internet sources. Boteraser aggregates this data solely for informational purposes and does not independently classify, evaluate, or endorse any findings about the vulnerabilities listed. The accuracy and completeness of this information is the sole responsibility of the original publishers. Boteraser and its operators accept no liability for any decisions made based on this data.

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