CVE-2021-3304
CVE-2021-3304 is a critical-severity vulnerability in Sagemcom F@st 3686 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: 1% (66th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-120
- Affected product: Sagemcom F@st 3686 Firmware
- Published:
- Last modified:
Description
Sagemcom F@ST 3686 v2 3.495 devices have a buffer overflow via a long sessionKey to the goform/login URI.
Frequently asked questions
- What is CVE-2021-3304?
- Sagemcom F@ST 3686 v2 3.495 devices have a buffer overflow via a long sessionKey to the goform/login URI.
- How severe is CVE-2021-3304?
- CVE-2021-3304 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-2021-3304 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-3304?
- CVE-2021-3304 affects Sagemcom F@st 3686 Firmware. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-3304?
- 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-2021-3304 published?
- CVE-2021-3304 was published on 2021-01-26 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:o:sagemcom:f\@st_3686_firmware:3.495:*:*:*:*:*:*:*
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