CVE-2021-36548
CVE-2021-36548 is a critical-severity vulnerability in Monstra with a CVSS 3.x base score of 9.8. 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: Critical (CVSS 3.x base score 9.8)
- CVSS v2: 7.5
- EPSS exploit prediction: 3% (88th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-434
- Affected product: Monstra
- Published:
- Last modified:
Description
A remote code execution (RCE) vulnerability in the component /admin/index.php?id=themes&action=edit_template&filename=blog of Monstra v3.0.4 allows attackers to execute arbitrary commands via a crafted PHP file.
Frequently asked questions
- What is CVE-2021-36548?
- A remote code execution (RCE) vulnerability in the component /admin/index.php?id=themes&action=edit_template&filename=blog of Monstra v3.0.4 allows attackers to execute arbitrary commands via a crafted PHP file.
- How severe is CVE-2021-36548?
- CVE-2021-36548 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2021-36548 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (88th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-36548?
- CVE-2021-36548 affects Monstra. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-36548?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
- When was CVE-2021-36548 published?
- CVE-2021-36548 was published on 2021-10-28 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:a:monstra:monstra:3.0.4:*:*:*:*:*:*:*
More vulnerabilities in Monstra
- CVE-2021-40940 — Critical (CVSS 9.8): Monstra 3.0.4 does not filter the case of php, which leads to an unrestricted file upload vulnerability.
- CVE-2020-25414 — Critical (CVSS 9.8): A local file inclusion vulnerability was discovered in the captcha function in Monstra 3.0.4 which allows remote…
- CVE-2020-13384 — High (CVSS 8.8): Monstra CMS 3.0.4 allows remote authenticated users to upload and execute arbitrary PHP code via…
- CVE-2018-16608 — High (CVSS 8.8): In Monstra CMS 3.0.4, an attacker with 'Editor' privileges can change the password of the administrator via an…
- CVE-2018-9037 — High (CVSS 8.8): Monstra CMS 3.0.4 allows remote code execution via an upload_file request for a .zip file, which is automatically…
- CVE-2018-6383 — High (CVSS 8.8): Monstra CMS through 3.0.4 has an incomplete "forbidden types" list that excludes .php (and similar) file extensions but…
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