Latest news with #CVE-2025-53779
Techday NZ
a day ago
- Techday NZ
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.
Tom's Guide
2 days ago
- Tom's Guide
Microsoft just fixed over 107 flaws including one serious zero-day — update your PC right now
Yesterday was Microsoft's August 2025 Patch Tuesday, and it was a busy one: The company issued patches for 107 total vulnerabilities including one zero-day flaw for an exploit in Windows Kerberos. Bleeping Computer reports that of the total flaws that were fixed, thirteen were rated critical. Of those thirteen critical flaws, nine were remote code execution style vulnerabilities, three were information disclosure attacks and one was an elevation of privilege. The style of bugs from the total number of vulnerabilities breaks down to: The zero-day vulnerability (tracked as CVE-2025-53779)is a Windows Kerberos Elevation of Privilege Vulnerability. It's a flaw in Kerberos that would permit authenticated hackers to have domain administrator privileges over a network. However, according to Microsoft, the attacker would require elevated access to two dMSA attributes in order to exploit the vulnerability. The two attributes are msds-groupMSAMembership, which would allow the user to utilize the dMSA and msds-ManagedAccountPreceededByLink, where the attacker needs write access to the attribute which allows them to specify a user that the dMSA can act on behalf of. Microsoft has attributed the discovery of the flaw to Yuval Gordon of Akamai who published a technical report on the flaw in May. Follow Tom's Guide on Google News to get our up-to-date news, how-tos, and reviews in your feeds. Make sure to click the Follow button. Get instant access to breaking news, the hottest reviews, great deals and helpful tips.
Techday NZ
3 days ago
- Techday NZ
August Patch Tuesday: Microsoft addressing 111 vulnerabilities
Microsoft is addressing 111 vulnerabilities this August 2025 Patch Tuesday, a volume which is around the recent average. In a neat parallel with last month, Microsoft is aware of public disclosure for a single one of the vulnerabilities published today, and claims no evidence of in-the-wild exploitation. Once again, the lone Patch Tuesday zero-day vulnerability is assessed as only moderate severity at time of publication, which brings Microsoft's lucky streak up to 11 months. Today's release includes the publication of nine critical remote code execution (RCE) vulnerabilities, although Microsoft has only marked one of these as more likely to see exploitation. Eight browser vulnerabilities have already been published separately this month, and are not included in the total. What do attackers want in a Windows context? Domain admin! When do they want it? Now! Today's lone zero-day vulnerability might be just what they need to break through the final layers of protection and swipe the crown jewels. CVE-2025-53779 is an elevation of privilege (EoP) vulnerability in the Windows implementation of Kerberos, which is enabled via abuse of dMSA configuration. The advisory FAQ provides more clues as to the nature of the attack than many comparable Microsoft advisories, but misses a golden opportunity for clarity, since it never sets out what it means by dMSA, leaving us scouring for contextual clues. Ultimately, we can determine from context that today's hot topic is the Delegated Managed Service Account, rather than the Defender Microservices Architecture or some other piece of Microsoft paraphernalia with matching initials. Microsoft's motivation is unimpeachable: the dMSA supports automated rotation of credentials for service accounts, and is specifically designed to prevent credential harvesting using Kerberoasting. Indeed, CISA has described Kerberoasting as one of the most time-efficient ways to elevate privileges and move laterally throughout an organisation's network. The good news here is that successful exploitation of CVE-2025-53779 requires an attacker to have pre-existing control of two attributes of the hopefully well protected dMSA: msds-groupMSAMembership, which determines which users may use credentials for the managed service account, and msds-ManagedAccountPrecededByLink, which contains a list of users on whose behalf the dMSA can act. However, abuse of CVE-2025-53779 is certainly plausible as the final link of a multi-exploit chain which stretches from no access to total pwnage. Finally, it's important to note that Microsoft is only publishing patches for Windows Server 2025, and that's because msds-ManagedAccountPrecededByLink was first implemented in Server 2025. Migrating to newer operating systems sooner rather than later remains good advice, but so is remediation of zero-day vulnerabilities which could give an attacker total control of your estate. The publication of any pre-authentication RCE in Windows will naturally spark discussion. Of course, not all pre-auth RCEs are created equal, and while CVE-2025-50165 has a hefty CVSSv3 base score of 9.8, and is certainly a cause for concern, it is not the worst of the worst, since it presumably isn't wormable. Despite that, a degree of alarm is amply justified, since the advisory FAQ mentions - twice! - that user interaction isn't required. Exploitation is via a malicious JPEG file, which could be delivered within an Office document or other means; perhaps even visiting a website would be sufficient, or receiving an email within Outlook, although the advisory doesn't explicitly confirm or deny these other possible attack routes. The malformed JPEG tricks the Windows Graphics Component into code execution via an untrusted pointer dereference. The context of execution isn't specified, so in the standard spirit of caution, we'll assume SYSTEM. This is hardly a new class of problem: we can cast our minds back a dozen years, for instance, and consider the broadly similar MS13-096. However, the specific flaw underlying CVE-2025-50165 is presumably a recent introduction, since only Windows 11 24H2 and Server 2025 receive patches. Patch this one sooner rather than later, since it could provide a skilled attacker with a valuable foothold from which to launch further attacks, including perhaps even today's CVE-2025-53779. The Windows GDI+ (Graphics Device Interface Plus) is at the centre of how almost all two-dimensional graphics are rendered on Windows assets. CVE-2025-53766 is a critical RCE in how GDI+ interprets metafiles, which are often used to store vector graphics. An attacker can achieve code execution via buffer overflow without privileges or user interaction. As with today's CVE-2025-50165, it's unlikely that this vulnerability could be wormable, but the most alarming path to exploitation involved simply uploading a malicious metafile to a Windows machine running unspecified web services. There is no mention of SharePoint, Exchange, Office, or other non-Windows products in the Security Updates section of the advisory, but that still leaves an essentially limitless potential attack surface; for example, anyone running a custom application offering file uploads could find themselves vulnerable to an attacker wielding a dodgy WMF file. On the bright side, the Preview Pane is not a vector in this case. A patch is available for Server 2008, but not Server 2012, a curious and possibly concerning pattern that we see from time to time with RCEs which affect the full historic range of Windows products. Today is certainly a good day for fans of critical RCE vulnerabilities which target weaknesses in how Windows interprets graphics. Exploitation of CVE-2025-50176, a flaw in the DirectX graphics kernel, could lead to execution in a kernel context. Microsoft considers exploitation more likely, which may be why the advisory doesn't provide a great deal of information about the means of exploitation, beyond a terse statement that type confusion is involved. Type confusion is where the kernel receives a pointer which it expects to be for one type of object, but is in fact for another, which is a bit like asking someone to read out loud from a restaurant menu, but then handing them their secret diary and hoping they won't notice the difference. Most people will not be fooled, but under the right circumstances, anything is possible. There are no significant changes to Microsoft product lifecycles this month. However, October will bring a flurry of changes, including the categorical end of support for non-LTSC versions of Windows 10.
