checkout-common-tokens
This report shows the evidence for checkout-common-tokens@20.1.6, the only known version.
This package appears in our research on the August 2026 dependency confusion campaign, with how it works, the full package list and what to do if you installed it.
OpenSSF/OSV Malicious Advisory
imported 2mo ago · by OpenSSF/OSVOpenSSF/OSV advisory MAL-2026-12351 confirms this npm version as malicious.
Advisory
MAL-2026-12351
Source
OpenSSF Malicious Packages via OSV
Summary
Malicious code in checkout-common-tokens (npm)
Details
On require, index.js loads _ext.js which selects a platform-specific payload URL from a rotating list of Cloudflare Workers subdomains (hosts assembled at runtime by joining split string fragments such as ["oob-worker.cf101-adf.workers.d","ev"].join("")), fetches the binary over HTTPS, writes it to /tmp/.cache_<hex> on Unix or %TEMP%\dotnet_diag_<hex>.exe on Windows, chmods 0o755, and spawns it detached via /bin/sh -c or cmd.exe. If the HTTPS fetch fails, _ext.js falls back to a DNS-TXT covert channel against *.dl.well1.site: a chunk-count TXT lookup at c.<domain> followed by N.<domain> TXT queries whose base64-decoded concatenation is written to disk and executed. Staging file names (.cache_*, dotnet_diag_*.exe,.analytics_state) are chosen to mimic legitimate diagnostic/telemetry artifacts, and destination hostnames are string-split obfuscated to defeat static inspection. The fetched payload is opaque, unpinned, unrelated to any documented package purpose, and executed with the installer's privileges immediately on import.
## Source: ghsa-malware (63365b713418a63ac55d381e309bd078a837b9059328608cf6c3619faafe6445) 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.
References
Source & flagged code
0 flagged · loading sourceNo flagged code excerpts are attached to this scan.
Findings
1 High
HighOsv Malicious Advisory
Affected versions and remediation
This report applies to checkout-common-tokens@20.1.6.
The versions list below shows the verdict for each recorded version.
- Avoid installing checkout-common-tokens@20.1.6. Remove it from direct dependencies and check your lockfile for transitive copies.
- Choose an independently verified alternative or release. This report does not establish that other versions are safe.
- If this version ran, investigate the affected machine and build environment. Rotate credentials it could access and rebuild from a trusted environment.
Evidence last updated: .
Source advisory published: .
This report uses published external intelligence. The advisory does not provide a separate source-code analysis for each listed version.
Think this verdict is wrong? Dispute it on GitHub or read how reports are produced.