CVE-2020-25853
The function CheckMic() in the Realtek RTL8195A Wi-Fi Module prior to versions released in April...
The function CheckMic() in the Realtek RTL8195A Wi-Fi Module prior to versions released in April 2020 (up to and excluding 2.08) does not validate the size parameter for an internal function, _rt_md5_hmac_veneer() or _rt_hmac_sha1_veneer(), resulting in a stack buffer over-read which can be exploited for denial of service. An attacker can impersonate an Access Point and attack a vulnerable Wi-Fi client, by injecting a crafted packet into the WPA2 handshake. The attacker does not need to know the network's PSK.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
The function CheckMic() in the Realtek RTL8195A Wi-Fi Module prior to versions released in April 2020 (up to and excluding 2.08) does not validate the size parameter for an internal function, _rt_md5_hmac_veneer() or _rt_hmac_sha1_veneer(), resulting in a stack buffer over-read which can be exploited for denial of service. An attacker can impersonate an Access Point and attack a vulnerable Wi-Fi client, by injecting a crafted packet into the WPA2 handshake. The attacker does not need to know the network's PSK.
- Record
CVE-2020-25853- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - CVSS 2.0
- 5.0 Medium
AV:N/AC:L/Au:N/C:N/I:N/A:P - Weakness
- CWE-126, CWE-125
- Updated
- 2026-11-02
CVE ListNo score
The function CheckMic() in the Realtek RTL8195A Wi-Fi Module prior to versions released in April 2020 (up to and excluding 2.08) does not validate the size parameter for an internal function, _rt_md5_hmac_veneer() or _rt_hmac_sha1_veneer(), resulting in a stack buffer over-read which can be exploited for denial of service. An attacker can impersonate an Access Point and attack a vulnerable Wi-Fi client, by injecting a crafted packet into the WPA2 handshake. The attacker does not need to know the network's PSK.
- Record
CVE-2020-25853- Weakness
- CWE-126
- Updated
- 2026-11-02
EUVDEUVD-2020-18486No score
The function CheckMic() in the Realtek RTL8195A Wi-Fi Module prior to versions released in April 2020 (up to and excluding 2.08) does not validate the size parameter for an internal function, _rt_md5_hmac_veneer() or _rt_hmac_sha1_veneer(), resulting in a stack buffer over-read which can be exploited for denial of service. An attacker can impersonate an Access Point and attack a vulnerable Wi-Fi client, by injecting a crafted packet into the WPA2 handshake. The attacker does not need to know the network's PSK.
- Record
EUVD-2020-18486- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-cf46-h25j-9pmqNo score
The function CheckMic() in the Realtek RTL8195A Wi-Fi Module prior to versions released in April...
The function CheckMic() in the Realtek RTL8195A Wi-Fi Module prior to versions released in April 2020 (up to and excluding 2.08) does not validate the size parameter for an internal function, _rt_md5_hmac_veneer() or _rt_hmac_sha1_veneer(), resulting in a stack buffer over-read which can be exploited for denial of service. An attacker can impersonate an Access Point and attack a vulnerable Wi-Fi client, by injecting a crafted packet into the WPA2 handshake. The attacker does not need to know the network's PSK.
- Record
GHSA-cf46-h25j-9pmq- Weakness
- CWE-125
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| facts | ||
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2020-25853 is a high vulnerability (CVSS 7.5) in Realtek Rtl8195a Firmware, published February 3, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.26%, the 70th percentile. No source names a fixed version.