Quick answers
- Is CVE-2026-112777 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-112777 being exploited in the wild.
- How severe is CVE-2026-112777?
- High severity, with a CVSS score of 7.2, published 19 October 2026.
- Which products and versions are affected?
- Craft CMS 4.x before 4.18.8, 5.x before 5.11.0.
- Is there a fix for CVE-2026-112777?
- Yes: fixed in 4.18.8, 5.11.0. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-112777 attacked?
- It is attacked over the network.
- Am I affected by CVE-2026-112777?
- Check whether you run Craft CMS 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
- Fixed in: 4.18.8, 5.11.0
Technical details
A case-sensitivity mismatch in the blocklist checks for Craft's Twig create() function allows attackers to instantiate SplFileObject by passing the class name in lowercase ("splfileobject"). The str_starts_with() and str_ends_with() checks are case-sensitive while PHP class resolution is case-insensitive, and the lowercase variant was removed from the case-insensitive blocklist. An attacker with template-execution rights (e.g., Control Panel administrator) can read arbitrary files or write PHP shells to achieve remote code execution.
Affected products
- Craft CMS 4.x before 4.18.8, 5.x before 5.11.0
Timeline
- 2026-10-05: disclosed
- 2026-10-19: advisory