Moquette is a lightweight Java MQTT broker. Prior to 0.18.1, PostOffice.publishWill publishes a client-controlled Last Will message through publish2Subscribers without invoking the authorizator.canWrite check used by normal PUBLISH paths. When anonymous access is enabled and topic ACLs restrict writes, a remote client can set an ACL-protected topic as the Last Will Topic during CONNECT and perform an abnormal client disconnect, causing the broker to inject attacker-controlled messages into a topic for which the client lacks write permission.
This issue is fixed in version 0.18.1.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Privileges Required
None
No privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
None
No data leak
Integrity
High
Complete data modification
Availability
None
No disruption
CVSS Vector v3.1
Weakness Type (CWE)
References 4
https://github.com/moquette-io/moquette/commit/e23df019f6a11e22c7d2047d4f86d070…
security-advisories@github.com
https://github.com/moquette-io/moquette/commit/f5a323fe782d1505c0097498cb22eb6e…
security-advisories@github.com
https://github.com/moquette-io/moquette/releases/tag/v0.18.1
security-advisories@github.com
https://github.com/moquette-io/moquette/security/advisories/GHSA-9jjc-fw8x-fmwx
security-advisories@github.com