CVE-2020-25853: realtek rtl8195a_firmware Buffer Over-read

Vulnerability summary

CVE-2020-25853 is a high (CVSS 7.5) Buffer Over-read vulnerability in realtek rtl8195a_firmware. EPSS estimates a 1.25% chance of exploitation in the next 30 days, higher than 68.9% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 03-02-2021
   PublishedVulnerability first disclosed.
2. 04-08-2024
   Last modifiedVulnerability information updated.

Description

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.

• CWE-126Buffer Over-readThe product reads from a buffer using buffer access mechanisms such as indexes or pointers that reference memory locations after the targeted buffer.
• CWE-125Out-of-bounds ReadThe product reads data past the end, or before the beginning, of the intended buffer.