# CVE-2023-38492: Kirby vulnerable to denial of service from unlimited password lengths > Attackers can cause denial of service by submitting excessively long passwords to the authentication endpoint, consuming server resources. - **Severity:** Medium 5.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L`) - **Exploited in the wild:** Not known - **Login needed:** Not needed - **Attackable:** Over the internet - **Victim action needed:** Not needed - **Fix available:** Yes - **Published:** 27 Jul 2023 - **Updated:** 22 Oct 2024 - **Also known as:** GHSA-3v6j-v3qc-cxff ## What is CVE-2023-38492? CVE-2023-38492 is a medium-severity denial of service vulnerability in getkirby kirby, published on 27 Jul 2023. An attacker can exploit it over the internet without logging in, with no action from the victim. ### Official description 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. Weakness: CWE-770 (Allocation of Resources Without Limits or Throttling) ## Which versions are affected by CVE-2023-38492? 10 open source packages ship an affected version, including getkirby/cms. It affects 1 product. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `getkirby/cms` | Packagist | All versions | 3.5.8.3 | | `getkirby/cms` | Packagist | All versions | 3.5.8.3 | | `getkirby/cms` | Packagist | From 3.6.0 | 3.6.6.3 | | `getkirby/cms` | Packagist | From 3.6.0 | 3.6.6.3 | | `getkirby/cms` | Packagist | From 3.7.0 | 3.7.5.2 | | `getkirby/cms` | Packagist | From 3.7.0 | 3.7.5.2 | | `getkirby/cms` | Packagist | From 3.8.0 | 3.8.4.1 | | `getkirby/cms` | Packagist | From 3.8.0 | 3.8.4.1 | | `getkirby/cms` | Packagist | From 3.9.0 | 3.9.6 | | `getkirby/cms` | Packagist | From 3.9.0 | 3.9.6 | Products: Getkirby Kirby. ## How do I fix CVE-2023-38492? Upgrade getkirby/cms to a fixed version for your release line: 3.5.8.3, 3.6.6.3, 3.7.5.2 or 3.8.4.1. ## Is CVE-2023-38492 being exploited? There is no known exploitation of CVE-2023-38492 in the wild and no public exploit code. ## Other vulnerabilities in getkirby kirby - [CVE-2024-26483](https://insights.sbomify.com/CVE-2024-26483/): Kirby vulnerable to unrestricted file upload of user avatar images (high 8.8) - [CVE-2024-41964](https://insights.sbomify.com/CVE-2024-41964/): Insufficient permission checks in the language settings in Kirby CMS (high 8.1) - [CVE-2026-34587](https://insights.sbomify.com/CVE-2026-34587/): Kirby has Server-Side Template Injection (SSTI) via double template resolution in option rendering (high 7.6) - [CVE-2021-29460](https://insights.sbomify.com/CVE-2021-29460/): Cross-site scripting (XSS) from unsanitized uploaded SVG files (high 7.6) - [CVE-2023-38489](https://insights.sbomify.com/CVE-2023-38489/): Kirby vulnerable to Insufficient Session Expiration after a password change (high 7.3) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2023-38492 and fix it if it is affected. What it is: CVE-2023-38492 is a medium-severity denial of service vulnerability in getkirby kirby, published on 27 Jul 2023. An attacker can exploit it over the internet without logging in, with no action from the victim. Exploitation: There is no known exploitation of CVE-2023-38492 in the wild and no public exploit code. Affected packages and fixed versions: - getkirby/cms (Packagist): affected all versions; fixed in 3.5.8.3 - getkirby/cms (Packagist): affected all versions; fixed in 3.5.8.3 - getkirby/cms (Packagist): affected from 3.6.0; fixed in 3.6.6.3 - getkirby/cms (Packagist): affected from 3.6.0; fixed in 3.6.6.3 - getkirby/cms (Packagist): affected from 3.7.0; fixed in 3.7.5.2 - getkirby/cms (Packagist): affected from 3.7.0; fixed in 3.7.5.2 - getkirby/cms (Packagist): affected from 3.8.0; fixed in 3.8.4.1 - getkirby/cms (Packagist): affected from 3.8.0; fixed in 3.8.4.1 - getkirby/cms (Packagist): affected from 3.9.0; fixed in 3.9.6 - getkirby/cms (Packagist): affected from 3.9.0; fixed in 3.9.6 Task: 1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies. 2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it. 3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead. 4. Run the tests and summarise what changed and why. 5. If nothing in the project is affected, say so and change nothing. Reference: https://insights.sbomify.com/CVE-2023-38492/ (Markdown: https://insights.sbomify.com/CVE-2023-38492/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2023-38492 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-38492 - OSV: https://osv.dev/vulnerability/CVE-2023-38492 --- From sbomify Insights: https://insights.sbomify.com/CVE-2023-38492/ Summaries are generated and may contain mistakes; the official description above is the record.