Author Topic: Let's encrypt certstream abuse often not detected...  (Read 465 times)

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Offline polonus

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Let's encrypt certstream abuse often not detected...
« on: January 27, 2023, 10:45:43 AM »
Widespread malicious pre-cert Let's Encrypt cert.chain abuse taking place.

Just a random example: https://host.io/nversia.ru
Also see: https://urlscan.io/result/be1fa059-766a-431d-b879-d04c9cbc73fe/#indicators

Not to say there are website certified there, that are well above board in these respects. :)

This particular cert. chaining abuse has been described here:
https://www.mike-gualtieri.com/posts/chaining-remote-web-vulnerabilities-to-abuse-lets-encrypt

Also Ahnlab described it as with: https://asec.ahnlab.com/en/45312/

Hope avast will also flag this kind of pre-chain certstream abuse (use CaliDog to detect).

Wonder whether the sponsors of letsencrypt dot org know,
where part of their money now goes to waste?

Source: luntrus, Bleeping Computer, etc.

polonus (volunteer 3rd party cold recon website security analyst and website error-hunter)

Cybersecurity is more of an attitude than anything else. Avast Evangelists.

Use NoScript, a limited user account and a virtual machine and be safe(r)!