CVE-2020-36109
CVE-2020-36109 is a critical-severity vulnerability in Asus Rt-ax86u Firmware 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-120.
Key facts
- Severity: Critical (CVSS 3.x base score 9.8)
- CVSS v2: 7.5
- EPSS exploit prediction: 4% (90th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-120
- Affected product: Asus Rt-ax86u Firmware
- Published:
- Last modified:
Description
ASUS RT-AX86U router firmware below version under 9.0.0.4_386 has a buffer overflow in the blocking_request.cgi function of the httpd module that can cause code execution when an attacker constructs malicious data.
Frequently asked questions
- What is CVE-2020-36109?
- ASUS RT-AX86U router firmware below version under 9.0.0.4_386 has a buffer overflow in the blocking_request.cgi function of the httpd module that can cause code execution when an attacker constructs malicious data.
- How severe is CVE-2020-36109?
- CVE-2020-36109 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-2020-36109 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (90th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2020-36109?
- CVE-2020-36109 affects Asus Rt-ax86u Firmware. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2020-36109?
- 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-2020-36109 published?
- CVE-2020-36109 was published on 2021-02-01 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:o:asus:rt-ax86u_firmware:*:*:*:*:*:*:*:*
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