Kirby vulnerable to denial of service from unlimited password lengths
- 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- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean?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 3.5.8.3, 3.6.6.3, 3.7.5.2, 3.8.41, 3.9.6, and 1 more
- 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
Kirby is a content management system. A vulnerability in versions prior to 3.5.8.3, 3.6.6.3, 3.7.5.2, 3.8.4.1, and 3.9.6 affects all Kirby sites with user accounts (unless Kirby's API and Panel are disabled in the config). The real-world impact of this vulnerability is limited, however we still recommend to update to one of the patch releases because they also fix more severe vulnerabilities. Kirby's authentication endpoint did not limit the password length. This allowed attackers to provide a password with a length up to the server's maximum request body length. Validating that password against the user's actual password requires hashing the provided password, which requires more CPU and memory resources (and therefore processing time) the longer the provided password gets. This could be abused by an attacker to cause the website to become unresponsive or unavailable. Because Kirby comes with a built-in brute force protection, the impact of this vulnerability is limited to 10 failed logins from each IP address and 10 failed logins for each existing user per hour. The problem has been patched in Kirby 3.5.8.3, 3.6.6.3, 3.7.5.2, 3.8.4.1, and 3.9.6. In all of the mentioned releases, the maintainers have added password length limits in the affected code so that passwords longer than 1000 bytes are immediately blocked, both when setting a password and when logging in.
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: none · Automatable: yes · Technical impact: partial
- Record last updated
Affected versions
- getkirby kirby
fixed in 3.5.8.3; From 3.6.0 · fixed in 3.6.6.3; From 3.7.0 · fixed in 3.7.5.2; From 3.8.0 · fixed in 3.8.41; From 3.9.0 · fixed in 3.9.6
- getkirby/cmsPackagist
fixed in 3.5.8.3
- getkirby/cmsPackagist
From 3.6.0 · fixed in 3.6.6.3
- getkirby/cmsPackagist
From 3.7.0 · fixed in 3.7.5.2
- getkirby/cmsPackagist
From 3.8.0 · fixed in 3.8.4.1
- getkirby/cmsPackagist
From 3.9.0 · fixed in 3.9.6