Ubuntu Fixes Radicale Authentication Attempt Handling
Tech GuruQuick Answer
Update Radicale on Ubuntu 16.04 LTS, restart the service, and validate failed-login handling and authorized calendar access.
Confirm Scope And Apply The Supported Remediation
What to do now: Inventory Ubuntu suite, installed radicale packages, repository origin, active consumers and owners. Match the installed suite and package to the official notice; assess upstream or bundled copies separately. Install the listed security packages through the supported Ubuntu repositories. Confirm required Ubuntu Pro, ESM or Legacy Support entitlements for older suites. Test CalDAV/CardDAV clients and authentication behavior; retain login logs, version records and configuration changes.
Last verified: 2026-11-13 UTC. Recheck the authoritative advisory and supported distribution channel before changing production.
Scope And Authority
| Product scope | Radicale calendar and address-book service on the Ubuntu releases listed in USN-9084-1 |
|---|---|
| Advisory | USN-9084-1 |
| CVE | CVE-2017-8342 |
| Authoritative release date | 2026-11-12 — November 12, 2026 at 20:54:41 UTC, from the official Ubuntu security feed; the notice gives the same date. |
| Authority revision date | No separate revision date is provided by the authority. |
| Affected versions | Ubuntu radicale packages on the suites listed in the fixed-version table, before their respective security updates. Applicability is package-, feature- and suite-specific. |
| Fixed version | 16.04 LTS: python-radicale, python3-radicale and radicale 1.1.1-1ubuntu0.1~esm1 |
| CVSS base score | Not provided by the authority |
| CVSS severity | Not provided by the authority |
| Exploitation status | The Ubuntu notice does not confirm exploitation in the wild.; no exploitation claim is inferred. |
What Changed
Missing delays after failed htpasswd authentication may expose passwords to timing or brute-force attacks.
What To Validate Now
- Inventory. Inventory Ubuntu suite, installed radicale packages, repository origin, active consumers and owners.
- Establish applicability. Match the installed suite and package to the official notice; assess upstream or bundled copies separately.
- Remediate. Install the listed security packages through the supported Ubuntu repositories. Confirm required Ubuntu Pro, ESM or Legacy Support entitlements for older suites.
- Validate. Test CalDAV/CardDAV clients and authentication behavior; retain login logs, version records and configuration changes.
- Retain evidence. Preserve asset and owner identifiers, the applicability decision, before-and-after versions, change approval, installation output, validation results, and any exception or rollback record.
Operational Cautions
Review authentication logs for unusual failures; patching alone does not determine whether credentials were exposed.
Evidence To Retain
- Exact product, release stream, package or application version, enabled feature, environment, and accountable owner.
- UTC timestamps, authority revision, approved change record, installer or package-manager output, and resulting version.
- Relevant logs and monitoring evidence, test results, exceptions, compensating controls, and rollback decisions.
Related TechGeeks Resources
Authoritative References
Correction policy: If the authority changes affected versions, fixed versions, severity, exploitation information, mitigations, or required action, TechGeeks will update this notice and its verification date.
