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

medium Affects typo3/cms-core. Feed 2026.10.29.1, updated 2026-10-28; published 2026-01-13; advisory modified 2026-02-03.

TYPO3 CMS Allows Insecure Deserialization via Mailer File Spool

Package: typo3/cms-core Composer
Affected versions: >=14.0.0 and <14.0.2 or >=13.0.0 and <13.4.23 or >=12.0.0 and <12.4.41 or >=11.0.0 and <11.5.49 or >=10.0.0 and <10.4.55
Fixed in: 14.0.2, 13.4.23, 12.4.41, 11.5.49, 10.4.55
Severity: medium
Exploitation: not on CISA KEV · EPSS 0% (7.9th percentile)
Published: 2026-01-13
Source: osv.dev

References

CWE-502

NVD record typo3/cms-core advisories

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