Denial of service from unlimited password lengths

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

5.3 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

EPSS

• CVE-2023-38492: 1.18% estimated exploitation activity in the next 30 days; percentile 67.68 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

TL;DR This vulnerability 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. ---- Introduction Denial of service (DoS) is a type of attack in which an attacker floods a service with the intention to limit performance or availability for legitimate users of the service. In the variation described in this advisory (a so called application layer denial of service attack), it is performed by causing a computationally expensive task to be run on the server. This may then cause a performance bottleneck. Impact 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…

Published by the source

28 Jul 2023, 15:34 UTC

Last modified by the source

5 Nov 2023, 05:01 UTC

Source last checked

26 Oct 2026, 14:10 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-3v6j-v3qc-cxff

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# Patch Next advisory brief: CVE-2023-38492

Advisory: Denial of service from unlimited password lengths
IDs: CVE-2023-38492, GHSA-3v6j-v3qc-cxff
Record: https://patchnext.com/advisories/cve-2023-38492 (revision 1, source checked 26 Oct 2026, 14:10 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 5.3)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: getkirby/cms 3.9.6, 3.8.4.1, 3.7.5.2, 3.6.6.3, 3.5.8.3. A vendor fix does not mean a deployment is fixed.

## Affected components
- Packagist getkirby/cms: affected < 3.5.8.3; >= 3.6.0, < 3.6.6.3; >= 3.7.0, < 3.7.5.2; >= 3.8.0, < 3.8.4.1; >= 3.9.0, < 3.9.6; fixed in 3.8.4.1, 3.7.5.2, 3.6.6.3, 3.9.6, 3.5.8.3

## Suggested inspection (read-only)
- Packagist getkirby/cms: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on getkirby/cms.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-3v6j-v3qc-cxff (GitHub-reviewed advisory GHSA-3v6j-v3qc-cxff lists affected ranges: Packagist getkirby/cms >=0 =3.6.0 =3.7.0 =3.8.0 =3.9.0 <3.9.6)

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