Vulnerability
Malicious code in instructor-mcp (PyPI)
--- _-= Per source details. Do not edit below this line.=-_ ## Source: amazon-inspector (6db8a103a73261cd6de8f763fa639d1bd148124ca661893e9d3ab73cd76ab50b) instructor-mcp 1.15.2 is a typosquat of the legitimate `instructor` PyPI library (it copies the same author names, README, and repository URL `github.com/instructor-ai/instructor`) and ships an additional file `instructor-setup.pth` that the Python interpreter auto-executes on every `python` invocation after install. The.pth file uses an obfuscated single-line `exec(...)` with mangled aliases (`_o,_s,_u,_p,_y,_h,_g`) to bypass the `.pth` rule that only `import` lines execute. The exec body downloads the Bun JavaScript runtime from `https://github.com/oven-sh/bun/releases/download/bun-v1.3.13/bun-{platform}-{arch}.zip` to `/tmp/b/bun`, chmods it executable, then searches `sys.path` for a file named `_index.js` and runs it via `bun run _index.js`. Execution is gated by `/tmp/.bun_ran` so it fires once per host. There is no hash/signature check on the downloaded runtime, and the JS payload is whatever `_index.js` happens to be present on `sys.path` (shipped by a co-installed package or planted by a separate component) — bypassing Python static analysis entirely. This is the alternate-runtime-dropper pattern: arbitrary attacker-controlled JS is executed under a freshly downloaded non-Python runtime, with persistence via the.pth auto-load mechanism. ## Source: kam193 (d22e882ab0d869a60fcff314b04f0534f3622d7719ed3a9101d55bb6c81dcbc9) Versions 1.15.2, 1.15.3 were compromised. Compromised packages start an obfuscated infostealer. The infostealer is a heavily obfuscated JavaScript code executed using Bun runtime on Python startup. It collectes all kinds of sensitive data, including API keys, credentials to package repositories, cryptocurrency assets, password manager data. Infostealer actively queries online services to collect additional secrets as well as attempts to gain persistence and spread further by publishing infected packages using collected credentials. Data are exfiltrated likely using Github. The code seems to threaten to wipe the user's data if it detects invalid GitHub tokens. Cleanup should be done with caution. It seems to be related to the recent Mini Shai Hulud campaign. --- Category: MALICIOUS - The campaign has clearly malicious intent, like infostealers. Campaign: 2026-06-compr-woodpecker Reasons (based on the campaign): - compromised-package - exfiltration-env-variables - exfiltration-cloud-tokens - exfiltration-credentials - abuses-pth - obfuscation - infostealer - The package contains code to detect if it is running in a sandbox environment. - exfiltration-crypto - files-exfiltration - destructive-actions
No CVSS base score from NVD or GHSA yet. NVD typically scores within 24–72 hours of publication; GHSA usually within a day for OSS-flagged CVEs. Last record update .
For interim severity, fall back on KEV / EXPLOIT signals and the EPSS percentile (lower panel). Re-check this CVE after one cron tick — the score lands automatically when the source publishes.
FIRST.org publishes EPSS daily. Coverage isn't universal — pre-disclosure CVEs and reserved IDs don't carry an EPSS score until at least one exploitation signal lands. Score will appear within 24 hours of the next EPSS pull.
No exploitation, limited impact or prevalence