CVE-2020-1027 is a Windows privilege escalation vulnerability in CSRSS. The root cause is a buffer overflow in the Side-by-Side (SxS) activation context code. Insufficient validation of a "UNICODE_STRING" before a "memcpy" allowed an attacker to trigger memory corruption and elevate privileges. It was exploited in the wild as part of a Chrome sandbox escape chain and is a great case study in CSRSS, SxS activation contexts, "UNICODE_STRING" handling, and secure memory validation. https://googleprojectzero.github.io/0days-in-the-wild/0day-RCAs/2020/CVE-2020-1027.html
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CVE-2020-1027 is a Windows privilege‑escalation flaw via buffer overflow in CSRSS SxS activation contexts, detailed in a Project Zero PoC and reported to have been used in the wild within a Chrome sandbox escape chain.