Quick answers
- Is CVE-2026-50279 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-50279 being exploited in the wild.
- How severe is CVE-2026-50279?
- High severity, with a CVSS score of 4, published 2 July 2026.
- Which products and versions are affected?
- craftcms/cms (Packagist) >= 5.0.0-RC1, < 5.9.21, ECOSYSTEM:introduced=5.0.0-RC1,fixed=5.9.21.
- Is there a fix for CVE-2026-50279?
- Yes. craftcms/cms (Packagist): upgrade to 5.9.21 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-50279 attacked?
- It is attacked over the network, in a network appliance.
- Am I affected by CVE-2026-50279?
- Check whether you run craftcms/cms (Packagist) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
How to fix
- craftcms/cms (Packagist): upgrade to 5.9.21 or later
composer require craftcms/cms:^5.9.21
Technical details
An improper authorization vulnerability exists in `EntriesController::actionSaveEntry()` due to a 'check-then-act' race-like logic gap. The controller enforces edit permissions on the original entry state before calling `_populateEntryModel()`, which processes attacker-supplied `authors` or `author` parameters. The `canChangeAuthor()` check is evaluated against the old authorship state; if the current user is an existing author, the change is permitted. Because the controller fails to re-verify authorization after the author list is mutated but before the element is saved, a user can reassign authorship to any other user without the `changeAuthorForPeerEntries` permission. This is fixed in version 5.9.21.
Affected products
- Pixel & Tonic Craft CMS >= 5.0.0-RC1, < 5.9.21
Identifiers
- CVE-2026-50279
- GHSA-qq2c-2q8j-jh27
Timeline
- 2026-05-29: disclosed
- 2026-07-02: advisory
- 2026-07-02: patched: Fixed in version 5.9.21