Which versions of oidcsessioncheck-enduser are malicious?

The following npm versions of oidcsessioncheck-enduser are flagged malicious: 99.0.0. Treat any of these as compromised.

How do I remediate oidcsessioncheck-enduser if I installed it?

Remove oidcsessioncheck-enduser from your project and lockfile, then assume any secrets accessible to the build or runtime were exposed: rotate API keys, tokens, and credentials, and audit for unexpected outbound activity or persistence.

I already installed oidcsessioncheck-enduser — how do I know if it already compromised me?

If oidcsessioncheck-enduser was installed, its post-install payload may already have run. Removing the package does not undo that — check outbound connections and credential use from the install window onward.

Is oidcsessioncheck-enduser part of a known attack campaign?

Yes — oidcsessioncheck-enduser is associated with the RLMA-2026-05185, RLUA-2026-06354 campaign. Packages in the same campaign often share infrastructure and payloads, so check whether any related packages are also in your dependency tree.

How do I find oidcsessioncheck-enduser across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for oidcsessioncheck-enduser (version 99.0.0).

Malicious package

oidcsessioncheck-endusernpm

Advisory published Jul 7, 2026Updated Sep 1, 2026

oidcsessioncheck-enduser is a confirmed malicious npm package (MAL-2026-7331) that executes malicious code on install (malicious version 99.0.0). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in oidcsessioncheck-enduser (npm)

MAL-2026-7331

Immediate action

Remove the package, then rotate any secrets the build/runtime could reach.

npm uninstall oidcsessioncheck-enduser

Malicious versions

1 flagged

99.0.0

Indicators of compromise (SHA-256)

f37558d3dd42626ee62580421b7463b742cac0d14ff92e751d3055fcab67cc52

206893f3713929ab522784d745b71728327dab5c7ac8c9090fd0c92c9acfcb2c

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for oidcsessioncheck-enduser (version 99.0.0).
If you installed it — respond
Remove oidcsessioncheck-enduser from your project and lockfile, then assume any secrets accessible to the build or runtime were exposed: rotate API keys, tokens, and credentials, and audit for unexpected outbound activity or persistence.
Did it already run?
If oidcsessioncheck-enduser was installed, its post-install payload may already have run. Removing the package does not undo that — check outbound connections and credential use from the install window onward.

Frequently asked questions

No. oidcsessioncheck-enduser on npm has been identified as a malicious package (version 99.0.0 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2026-05185RLUA-2026-06354

References

github.com

Credits

ReversingLabs · finder

Detect & block this

O3 blocks oidcsessioncheck-enduser-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the malicious outbound activity and severs the channel.

Malware detection Runtime egress monitoring

Explore

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