How severe is CVE-2017-14251?

CVE-2017-14251 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2017-14251 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (81st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2017-14251?

CVE-2017-14251 primarily affects Typo3. In total, 42 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2017-14251?

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.

When was CVE-2017-14251 published?

CVE-2017-14251 was published on 2017-09-11 and last updated on 2026-06-17.

CVE-2017-14251

CVE-2017-14251 is a high-severity vulnerability in Typo3 with a CVSS 3.x base score of 8.8. 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-434.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 6.5
EPSS exploit prediction: 2% (81st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-434
Affected product: Typo3
Published: 2017-09-11
Last modified: 2026-06-17

Description

Unrestricted File Upload vulnerability in the fileDenyPattern in sysext/core/Classes/Core/SystemEnvironmentBuilder.php in TYPO3 7.6.0 to 7.6.21 and 8.0.0 to 8.7.4 allows remote authenticated users to upload files with a .pht extension and consequently execute arbitrary PHP code.

Frequently asked questions

What is CVE-2017-14251?: Unrestricted File Upload vulnerability in the fileDenyPattern in sysext/core/Classes/Core/SystemEnvironmentBuilder.php in TYPO3 7.6.0 to 7.6.21 and 8.0.0 to 8.7.4 allows remote authenticated users to upload files with a .pht extension and consequently execute arbitrary PHP code.
How severe is CVE-2017-14251?: CVE-2017-14251 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2017-14251 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (81st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2017-14251?: CVE-2017-14251 primarily affects Typo3. In total, 42 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2017-14251?: 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.
When was CVE-2017-14251 published?: CVE-2017-14251 was published on 2017-09-11 and last updated on 2026-06-17.

References

Affected products (42)

cpe:2.3:a:typo3:typo3:7.6.0:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:7.6.1:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:7.6.2:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:7.6.3:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:7.6.4:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:7.6.5:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:7.6.6:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:7.6.7:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:7.6.8:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:7.6.9:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:7.6.10:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:7.6.11:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:7.6.12:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:7.6.13:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:7.6.14:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:7.6.15:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:7.6.16:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:7.6.17:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:7.6.18:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:7.6.19:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:7.6.20:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:7.6.21:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:8.0.0:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:8.0.1:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:8.1.0:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:8.1.1:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:8.1.2:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:8.2.0:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:8.2.1:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:8.3.0:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:8.3.1:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:8.4.0:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:8.4.1:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:8.5.0:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:8.5.1:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:8.6.0:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:8.6.1:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:8.7.0:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:8.7.1:*:*:*:*:*:*:*
cpe:2.3:a:typo3:typo3:8.7.2:*:*:*:*:*:*:*

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