How severe is CVE-2026-0859?

CVE-2026-0859 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-0859 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (6th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-0859?

CVE-2026-0859 affects Typo3. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-0859?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2026-0859 have an EU (EUVD) identifier?

Yes. CVE-2026-0859 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-2014.

When was CVE-2026-0859 published?

CVE-2026-0859 was published on 2026-01-13 and last updated on 2026-06-17.

CVE-2026-0859

CVE-2026-0859 is a high-severity vulnerability in Typo3 with a CVSS 3.x base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-502.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v4: 5.2
EPSS exploit prediction: 0% (6th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-2014
Weakness: CWE-502
Affected product: Typo3
Published: 2026-01-13
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2026-0859?: 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.
How severe is CVE-2026-0859?: CVE-2026-0859 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-0859 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (6th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-0859?: CVE-2026-0859 affects Typo3. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-0859?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-0859 have an EU (EUVD) identifier?: Yes. CVE-2026-0859 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-2014.
When was CVE-2026-0859 published?: CVE-2026-0859 was published on 2026-01-13 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:typo3:typo3:*:*:*:*:*:*:*:*

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