CVE-2021-39306
CVE-2021-39306 is a critical-severity vulnerability in Realtek Rtl8195am 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-787.
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-787
- Affected product: Realtek Rtl8195am Firmware
- Published:
- Last modified:
Description
A stack buffer overflow was discovered on Realtek RTL8195AM device before 2.0.10, it exists in the client code when an attacker sends a big size Authentication challenge text in WEP security.
Frequently asked questions
- What is CVE-2021-39306?
- A stack buffer overflow was discovered on Realtek RTL8195AM device before 2.0.10, it exists in the client code when an attacker sends a big size Authentication challenge text in WEP security.
- How severe is CVE-2021-39306?
- CVE-2021-39306 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-2021-39306 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-2021-39306?
- CVE-2021-39306 affects Realtek Rtl8195am Firmware. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-39306?
- 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-2021-39306 published?
- CVE-2021-39306 was published on 2021-12-22 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:o:realtek:rtl8195am_firmware:*:*:*:*:*:*:*:*
More vulnerabilities in Realtek Rtl8195am Firmware
- CVE-2021-43573 — Critical (CVSS 9.8): A buffer overflow was discovered on Realtek RTL8195AM devices before 2.0.10. It exists in the client code when…
- CVE-2020-9395 — High (CVSS 8.0): An issue was discovered on Realtek RTL8195AM, RTL8711AM, RTL8711AF, and RTL8710AF devices before 2.0.6. A stack-based…
- CVE-2022-34326 — High (CVSS 7.5): In ambiot amb1_sdk (aka SDK for Ameba1) before 2022-06-20 on Realtek RTL8195AM devices before…
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