Hackers target Microsoft SharePoint RCE chain with PoC exploit

Attackers are targeting a chain of two Microsoft SharePoint vulnerabilities that may allow arbitrary code execution on unpatched servers. Public proof-of-concept (PoC) exploits are available for both vulnerabilities. Defused reported that the CVE-2026-55040 exploit code had been weaponized for attacks and later observed the chain being probed in honeypots; no code execution had been observed there at that time.