[CVE-2026-63520]

August 25, 2026

• Rapid7 published analysis of SharePoint RCE CVE-2026-63520. CERT-EU's updated advisory covers the wider on-prem SharePoint chain, noting public PoC code and observed exploitation of CVE-2026-50522 alongside CVE-2026-32201, CVE-2026-45659, CVE-2026-56164 and CVE-2026-58644 — and recommends rotating credentials on any exposed server, not just patching (Rapid7, CERT-EU). · Vulnerabilities & Exploits

in The Rogue Agent Staged an Apology, Then Pushed More Malware

August 13, 2026

• SharePoint auth-bypass CVE-2026-55040 is now being exploited in the wild shortly after Rapid7 dropped a PoC on Patch Tuesday. The flaw stems from improper JWT validation that lets an attacker forge unsigned tokens and impersonate any user, including admins, and chains with the RCE flaw CVE-2026-63520 (earlier coverage). See BleepingComputer, Rapid7's technical analysis, and Viettel's writeup. · Offensive & Exploitation

in ShieldBreak Turns a "Patched" Defender Bug Back Into SYSTEM

August 12, 2026

• Rapid7 disclosed an AI-assisted SharePoint exploit chain reaching unauthenticated RCE, tracked as CVE-2026-63520, discovered during a 0-day research project against the platform (The Hacker News). Separately, CISA confirmed ransomware crews are now abusing a high-severity SharePoint RCE that has been flagged as exploited since early July (BleepingComputer). · AI, Agents & Offensive Security

in When the AI Is the One Finding the Zero-Days