CVE-2026-49740: TYPO3 CMS - Insecure Deserialization in Core API

Severity: medium (CVSS 6.3 v4.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-06-09 · updated 2026-07-23
Weakness: CWE-502

Description

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. This issue affects TYPO3 CMS versions before 10.4.57, 11.0.0-11.5.50, 12.0.0-12.4.45, 13.0.0-13.4.30 and 14.0.0-14.3.2.

Affected products

typo3: before 10.4.57; from 11.0.0 before 11.5.51; from 12.0.0 before 12.4.46; from 13.0.0 before 13.4.31; from 14.0.0 before 14.3.3 — fixed in 10.4.57, 11.5.51, 12.4.46, 13.4.31, 14.3.3

How to fix

Upgrade to a fixed version: typo3 10.4.57, 11.5.51, 12.4.46, 13.4.31. Check the vendor advisory for mitigations.

References

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