16 hours ago
SharePoint flaw sparks urgent patch call amid new RCE threat
Cybersecurity experts are urging organisations to take immediate action following the disclosure of a critical vulnerability in Microsoft SharePoint, as highlighted in the latest Patch Tuesday security update. This newly identified issue, designated CVE-2025-49712, is raising alarms given its potential to facilitate remote code execution (RCE) when combined with other known flaws.
Saeed Abbasi, Senior Manager of Security Research at Qualys Threat Research Unit, described the vulnerability as a significant threat, especially coming on the heels of last month's "ToolShell" zero-day attacks. Abbasi commented, "This RCE demands authentication but pairs dangerously with known authentication bypasses. Attackers chaining this with prior flaws could achieve full server compromise, and data exfiltration." He added that while there have been no reports of exploitation in the wild so far, experience suggests such gaps can be closed rapidly as threat actors adapt their techniques.
Abbasi urged organisations to "prioritise and patch all SharePoint updates, rotate keys, and eliminate internet exposure," stressing that delaying mitigation efforts could trigger both regulatory scrutiny and significant data breaches. "SharePoint's exploit streak isn't over," Abbasi warned, underscoring the need for proactive management of the platform's security posture.
The August Patch Tuesday update from Microsoft addressed a total of 107 Common Vulnerabilities and Exposures (CVEs). Of these, 13 were rated critical and 91 as important. Elevation of privilege (EoP) vulnerabilities accounted for 39.3% of the fixes, while remote code execution issues made up 32.7% - a pattern consistent with trends observed in previous months.
Satnam Narang, Senior Staff Research Engineer at Tenable, noted that "this month's release highlights an upward trend in post-compromise vulnerabilities over code execution bugs. For the second consecutive month, elevation of privilege vulnerabilities represented the bulk of CVEs patched this month." Narang referred to the patch for CVE-2025-53779, a privilege escalation flaw known as BadSuccessor, describing its immediate impact as limited due to the specific prerequisites needed for exploitation. "An attacker must have at least one domain controller in a domain running Windows Server 2025 in order to achieve domain compromise," he explained, making it a targeted rather than broad-based risk.
SharePoint vulnerabilities continued to receive particular attention, with Narang observing, "It might seem like déjà vu because Microsoft patched two more SharePoint vulnerabilities this month: a remote code execution flaw (CVE-2025-49712) and an elevation of privilege bug (CVE-2025-53760). After the chaos that ensued with the exploitation of the ToolShell vulnerabilities, any new SharePoint vulnerabilities understandably raise concerns."
Since 2022, Microsoft has patched an average of 21.7 SharePoint vulnerabilities annually, with 2023 seeing a high of 25. With 20 already addressed in the current year, the record may soon be exceeded, according to Narang. Despite this volume of patches, he noted, "only three were exploited in the wild (CVE-2023-29357, CVE-2023-24955, CVE-2024-38094) in addition to the three ToolShell vulnerabilities (CVE-2025-49706, CVE-2025-49704, CVE-2025-53770)," though another, CVE-2025-53771, may also have been exploited based on emerging reports.
Security practitioners highlight the recurring threat presented by SharePoint vulnerabilities, which can serve as gateways for lateral movement and deeper network compromise if not promptly addressed. With a rising tally of disclosed flaws and only a handful exploited so far, experts are calling for continued vigilance, patching discipline, and the hardening of exposed enterprise collaboration systems.
