Insufficient session invalidation in Kanboard
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 1.2.43
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
- Exploitation: none
- Automatable: yes
- Technical impact: partial
Summary
Kanboard is project management software that focuses on the Kanban methodology. In affected versions sessions are still usable even though their lifetime has exceeded. Kanboard implements a cutom session handler (`app/Core/Session/SessionHandler.php`), to store the session data in a database. Therefore, when a `session_id` is given, kanboard queries the data from the `sessions` sql table. At this point, it does not correctly verify, if a given `session_id` has already exceeded its lifetime (`expires_at`). Thus, a session which's lifetime is already `> time()`, is still queried from the database and hence a valid login. The implemented SessionHandlerInterface::gc function, that does remove invalid sessions, is called only with a certain probability (_Cleans up expired sessions. Called by `session_start()`, based on `session.gc_divisor`, `session.gc_probability` and `session.gc_maxlifetime` settings_) accordingly to the php documentation. In the official Kanboard docker image these values default to: session.gc_probability=1, session.gc_divisor=1000. Thus, an expired session is only terminated with probability 1/1000. This issue has been addressed in release 1.2.43 and all users are advised to upgrade. There are no known workarounds for this vulnerability.
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: none · Automatable: yes · Technical impact: partial
- Record last updated
Affected versions
- kanboard kanboard
fixed in 1.2.43