USN-9084-1: Radicale vulnerability
Publication date
12 November 2026
Overview
Radicale could be made to expose sensitive information over the network.
Releases
Packages
- radicale - simple calendar and addressbook server
Details
It was discovered that Radicale did not delay failed authentication
attempts when using htpasswd authentication. A remote attacker could
possibly use this issue to obtain user passwords through timing or
brute-force attacks.
It was discovered that Radicale did not delay failed authentication
attempts when using htpasswd authentication. A remote attacker could
possibly use this issue to obtain user passwords through timing or
brute-force attacks.
Update instructions
After a standard system update you need to restart Radicale to make all the necessary changes.
Learn more about how to get the fixes.The problem can be corrected by updating your system to the following package versions:
| Ubuntu Release | Package Version | ||
|---|---|---|---|
| 16.04 LTS xenial | python-radicale – 1.1.1-1ubuntu0.1~esm1 | ||
| python3-radicale – 1.1.1-1ubuntu0.1~esm1 | |||
| radicale – 1.1.1-1ubuntu0.1~esm1 | |||
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