CVE-2026-49740
TYPO3 CMS has Insecure Deserialization via Core API
Description
### Problem TYPO3's cache frontend (`VariableFrontend`) and persistent key-value store (`Registry`) deserialized PHP payloads without integrity validation or class restrictions. An attacker with write access to the underlying storage backend (cache store or sys_registry database table) could inject a crafted serialized payload to trigger PHP Object Injection, potentially exploiting a gadget chain to achieve Remote Code Execution or other high-impact effects. Exploiting this vulnerability requires direct local write access to the storage, such as the SQL database or file system. ### Solution Update to TYPO3 versions 10.4.57 ELTS, 11.5.51 ELTS, 12.4.46 ELTS, 13.4.31 LTS, 14.3.3 LTS that fix the problem described. ### Credits TYPO3 CMS thanks “z3rco”, Chowdhury Faizal Ahammed, Rick Larabee, Vitaly Simonovich, Nozomu Sasaki, Mert Akdag, “tikket”, Shafi Almutairi for reporting this issue, and to TYPO3 core & security team member Oliver Hader for fixing it. ### Resources * [TYPO3-CORE-SA-2026-018](https://typo3.org/security/advisory/typo3-core-sa-2026-018)
How to fix CVE-2026-49740
To remediate CVE-2026-49740, upgrade the affected package to a fixed version below.
- —upgrade to 10.4.57 or later
Is CVE-2026-49740 being exploited?
No exploitation signal available. Neither CISA KEV nor a current EPSS score has been published for CVE-2026-49740.
Affected packages (1)
- from 0, < 10.4.57
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 4.0 | — | CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:H/SI:H/SA:H |