How severe is CVE-2018-13356?

CVE-2018-13356 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-2018-13356 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-13356?

CVE-2018-13356 affects Terra-master Terramaster Operating System. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-13356?

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-2018-13356 published?

CVE-2018-13356 was published on 2018-11-27 and last updated on 2026-06-17.

CVE-2018-13356

CVE-2018-13356 is a high-severity vulnerability in Terra-master Terramaster Operating System 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-863.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 9.0
EPSS exploit prediction: 2% (78th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-863
Affected product: Terra-master Terramaster Operating System
Published: 2018-11-27
Last modified: 2026-06-17

Description

Incorrect access control on ajaxdata.php in TerraMaster TOS version 3.1.03 allows attackers to elevate user permissions.

Frequently asked questions

What is CVE-2018-13356?: Incorrect access control on ajaxdata.php in TerraMaster TOS version 3.1.03 allows attackers to elevate user permissions.
How severe is CVE-2018-13356?: CVE-2018-13356 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-2018-13356 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-13356?: CVE-2018-13356 affects Terra-master Terramaster Operating System. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-13356?: 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-2018-13356 published?: CVE-2018-13356 was published on 2018-11-27 and last updated on 2026-06-17.

References

https://blog.securityevaluators.com/vulnerabilities-in-terramaster-tos-3-1-03-fb99cf88b86a

Affected products (1)

cpe:2.3:o:terra-master:terramaster_operating_system:3.1.03:*:*:*:*:*:*:*

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