Which versions of Blazor.Captcha are malicious?

The following NuGet versions of Blazor.Captcha are flagged malicious: 1.4.2, 1.4.3. Treat any of these as compromised.

How do I remediate Blazor.Captcha if I installed it?

Remove Blazor.Captcha 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 Blazor.Captcha — how do I know if it already compromised me?

If Blazor.Captcha 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 Blazor.Captcha part of a known attack campaign?

Yes — Blazor.Captcha is associated with the RLMA-2024-03159 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 Blazor.Captcha across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for Blazor.Captcha (2 malicious versions).

Malicious package

Blazor.CaptchaNuGet

Blazor.Captcha is a confirmed malicious NuGet package (MAL-2024-4312) that executes malicious code on install (malicious versions 1.4.2, 1.4.3). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in Blazor.Captcha (NuGet)

MAL-2024-4312

Immediate action

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

remove Blazor.Captcha

Malicious versions

2 flagged

1.4.21.4.3

Indicators of compromise (SHA-256)

19e0480cbe5f041b6bcfaf733ef9dee47d92047cb02cfc02bedf1aa52af84e3b

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for Blazor.Captcha (2 malicious versions).
If you installed it — respond
Remove Blazor.Captcha 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 Blazor.Captcha 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. Blazor.Captcha on NuGet has been identified as a malicious package (versions 1.4.2, 1.4.3 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2024-03159

Credits

ReversingLabs · finder

Detect & block this

O3 blocks Blazor.Captcha-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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