CVE-2026-0859: TYPO3 CMS Allows Insecure Deserialization via Mailer File Spool

Description

TYPO3's mail‑file spool deserialization flaw lets local users with write access to the spool directory craft a malicious file that is deserialized during the mailer:spool:send command, enabling arbitrary PHP code execution on the web server. This issue affects TYPO3 CMS versions 10.0.0-10.4.54, 11.0.0-11.5.48, 12.0.0-12.4.40, 13.0.0-13.4.22 and 14.0.0-14.0.1.

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Attack vector

Local

Complexity

Low

Privileges

Low

User interaction

None

Confidentiality

High

Integrity

High

Availability

High

Scope

Unchanged

Exploitation

Is it being used?

Exploit prediction (EPSS)0.2% · higher than 8% of CVEs

Exploited in the wildNo evidence yet

CISA KEVNot listed

Ransomware campaign useNot known

Affected products

Which versions

TC

TYPO3 CMS · TYPO3

10.0.0 before 10.4.55; 11.0.0 before 11.5.49; 12.0.0 before 12.4.41; 13.0.0 before 13.4.23; 14.0.0 before 14.0.2 · source: vendor

TY

Typo3 · Typo3

10.0.0 before 10.4.55; 11.0.0 before 11.5.49; 12.0.0 before 12.4.41; 13.0.0 before 13.4.23; 14.0.0 before 14.0.2 · source: NVD