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A newly discovered zero-day vulnerability in Microsoft Exchange, tracked as CVE-2026-42897, poses a significant risk as it allows attackers to exploit cross-site scripting (XSS) to compromise Outlook Web Access (OWA) mailboxes. This vulnerability is reportedly under active attack, meaning that malicious actors are currently trying to exploit it in the wild. Organizations using Microsoft Exchange should be particularly vigilant, as the absence of an available patch leaves their systems exposed. Without immediate remediation, users could face unauthorized access to sensitive email communications. Companies are advised to implement security measures, such as input validation and monitoring for suspicious activity, until an official patch is released.

Microsoft has confirmed that a new zero-day vulnerability in Exchange Server, identified as CVE-2026-42897, is being actively exploited by attackers. This vulnerability has a CVSS score of 8.1, indicating a high level of severity. It stems from improper handling of user input during web page generation, which can lead to cross-site scripting (XSS) attacks. Organizations using affected versions of Exchange Server are at risk, as attackers could exploit this flaw to execute malicious scripts in the context of users' browsers. Microsoft urges users to take immediate action to protect their systems and data from potential breaches.

Microsoft has issued a warning about a serious cross-site scripting (XSS) vulnerability, identified as CVE-2026-42897, affecting on-premises versions of Microsoft Exchange Server. This vulnerability allows unauthorized attackers to spoof users over a network, posing significant risks to organizations that have not yet applied any fixes. The affected versions include Microsoft Exchange Server Subscription Edition RTM, 2019, and 2016, while Exchange Online remains unaffected. Microsoft is currently working on a permanent fix, but until it is released, they have provided temporary mitigations for users to implement. Organizations using the affected versions should take immediate action to safeguard their systems from potential exploitation.

A recent cybersecurity incident involving the online learning platform Canvas has raised concerns after the hacking group ShinyHunters successfully breached the system twice. The attackers exploited vulnerabilities through cross-site scripting (XSS) and compromised user identities, leading to the exposure of sensitive student data. In response to these breaches, a House committee chair has called for Instructure, the parent company of Canvas, to testify about the incident. This situation is significant as it not only affects students' personal information but also raises questions about the security measures in place to protect educational platforms. The potential for misuse of the exposed data could have far-reaching implications for students and educational institutions alike.

Researchers have identified that over 10,000 instances of the Zimbra Collaboration Suite (ZCS) are exposed to the internet and are vulnerable to ongoing cross-site scripting (XSS) attacks. This security flaw allows attackers to execute malicious scripts in users' browsers, which can lead to unauthorized access to sensitive information. The affected servers could be utilized by various organizations for email and collaboration services, making them prime targets for exploitation. The ongoing nature of these attacks means that users and administrators should take immediate action to secure their systems. Ignoring this vulnerability could lead to severe data breaches and loss of confidential information.

A Russian advanced persistent threat (APT) group has been exploiting a critical cross-site scripting (XSS) vulnerability in Zimbra, identified as CVE-2025-66376, with a severity score of 7.2. The attackers are sending HTML emails that contain insufficiently sanitized scripts, which execute when opened by users. This campaign specifically targets individuals in Ukraine, highlighting the ongoing cyber conflict in the region. The exploitation of this vulnerability could allow attackers to compromise user accounts and access sensitive information. Organizations using Zimbra should be particularly vigilant and take immediate action to secure their systems.

The Cybersecurity and Infrastructure Security Agency (CISA) has directed U.S. federal agencies to address a vulnerability in the Zimbra Collaboration Suite (ZCS) that is currently being exploited in the wild. This flaw allows for cross-site scripting attacks, which can enable attackers to execute malicious scripts in the context of a user's session. Affected organizations need to act quickly to secure their servers to prevent unauthorized access and data breaches. The urgency of this directive underscores the importance of maintaining up-to-date security practices, especially for government entities that handle sensitive information. Users of ZCS should ensure their systems are patched as soon as possible to mitigate the risk posed by this vulnerability.

Researchers have identified a cross-site scripting (XSS) vulnerability in the control panel of StealC malware, an infostealer that has been operating since at least 2023. This malware, which is sold as a service, targets and extracts sensitive information like cookies and passwords from victims. The flaw in the control panel has exposed important details about the attackers behind the malware, raising concerns about the ongoing threat to users' data security. Since its update to StealC v2 in 2025, the malware has continued to pose risks to individuals and organizations alike. The discovery emphasizes the need for vigilance against such malware, as the information leak could lead to further malicious activities by the attackers.

Researchers discovered a cross-site scripting (XSS) vulnerability in the web-based control panel of the StealC info-stealing malware. This flaw allowed them to monitor the malware operators' active sessions and collect data on their hardware setups. StealC is designed to steal sensitive information from users, which means this incident not only exposes the attackers but also raises concerns about the ongoing effectiveness of such malware. Understanding these vulnerabilities can help cybersecurity experts develop better defenses against similar threats. The incident serves as a reminder that even sophisticated malware can have weaknesses that researchers can exploit to gain insights into cybercriminal operations.