CVE-2026-55040 - Geek Feed

Hackers target Microsoft SharePoint RCE chain with PoC exploit

August 29, 2026August 29, 2026 geekfeed0Tagged Authentication Bypass, CVE-2026-55040, CVE-2026-63520, exploit, microsoft, Microsoft SharePoint, Proof of Concept, Remote Code Execution, Warning

Attackers are now targeting a chain of two Microsoft SharePoint vulnerabilities that can allow them to execute arbitrary code on unpatched servers, according to threat intelligence company Defused. The first (tracked as CVE-2026-55040) is an authentication bypass flaw in the JWT token validation pipeline that attackers without privileges can exploit to perform operations as a SharePoint […]

2 mins read

Hackers leverage new Microsoft SharePoint exploit in attacks

August 14, 2026August 14, 2026 geekfeed1Tagged Actively Exploited, Authentication Bypass, bypass, CVE-2026-55040, exploit, Microsoft SharePoint, Proof of Concept

A proof-of-concept (PoC) exploit for a critical Microsoft SharePoint vulnerability, published by cybersecurity company Rapid7 on Tuesday, is already being used in attacks. Tracked as CVE-2026-55040, this authentication bypass security flaw in the JWT token validation pipeline can be exploited by attackers without privileges to perform operations as a SharePoint site user or administrator. Microsoft patched […]

2 mins read