ToolShell: a story of five vulnerabilities in Microsoft SharePoint


On July 19–20, 2025, various security companies and national CERTs published alerts about active exploitation of on-premise SharePoint servers. According to the reports, observed attacks did not require authentication, allowed attackers to gain full control over the infected servers, and were performed using an exploit chain of two vulnerabilities:

CVE-2025-49704 and CVE-2025-49706, publicly named “ToolShell”. Additionally, on the same dates, Microsoft released out-of-band security patches for the vulnerabilities CVE-2025-53770 and CVE-2025-53771, aimed at addressing the security bypasses of previously issued fixes for CVE-2025-49704 and CVE-2025-49706. The release of the new, “proper” updates has caused confusion about exactly which vulnerabilities attackers are exploiting and whether they are using zero-day exploits.

Read more…
Source: Kaspersky


Sign up for the Cyber Security Review Newsletter
The latest cyber security news and insights delivered right to your inbox


Related:

  • NSA: Top 25 vulnerabilities actively abused by Chinese hackers

    October 19, 2020

    The U.S. National Security Agency (NSA) warns that Chinese state-sponsored hackers exploit 25 different vulnerabilities in attacks against U.S. organizations and interests. In an advisory issued today, the NSA said that it is aware of targeted attacks by Chinese state-sponsored hackers against National Security Systems (NSS), the U.S. Defense Industrial Base (DIB), and the Department of ...

  • Operation Earth Kitsune, Tracking SLUB’s Current Operations

    October 19, 2020

    Trend Micro have already published findings on the SLUB malware’s past campaigns. In our latest research paper, we uncovered a recent watering hole campaign that involves a new variant of the malware. The threat, which we dubbed as such due to its abuse of Slack and GitHub in previous versions, has not abused either of ...

  • Three npm packages found opening shells on Linux, Windows systems

    October 19, 2020

    Three JavaScript packages have been removed from the npm portal on Thursday for containing malicious code. According to advisories from the npm security team, the three JavaScript libraries opened shells on the computers of developers who imported the packages into their projects. The shells, a technical term used by cyber-security researchers, allowed threat actors to connect remotely ...

  • Ryuk Ransomware Gang Uses Zerologon Bug for Lightning-Fast Attack

    October 19, 2020

    The Ryuk threat actors have struck again, moving from sending a phishing email to complete encryption across the victim’s network in just five hours. That breakneck speed is partially the result of the gang using the Zerologon privilege-escalation bug (CVE-2020-1472), less than two hours after the initial phish, researchers said. The Zerologon vulnerability allows an unauthenticated attacker ...

  • Bug bounty reporter cashes out on someone else’s exploit

    October 19, 2020

    Bug bounty programs have gained increased momentum and interest from the security research community for their role in promoting security awareness and responsible vulnerability disclosure. But they are not without their fair share of problems. Bug bounty platforms fill a genuine need. They help companies solicit vulnerability reports in their products from pen-testers and researchers in ...

  • 800,000 SonicWall VPNs vulnerable to new remote code execution bug

    October 16, 2020

    Almost 800,000 internet-accessible SonicWall VPN appliances will need to be updated and patched for a major new vulnerability that was disclosed on Wednesday. Discovered by the Tripwire VERT security team, CVE-2020-5135 impacts SonicOS, the operating system running on SonicWall Network Security Appliance (NSA) devices. SonicWall NSAs are used as firewalls and SSL VPN portals to filter, control, ...