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Fortinet has begun releasing security updates to address a critical flaw impacting FortiOS that has come under active exploitation in the wild. The vulnerability, assigned the CVE identifier CVE-2026-24858 (CVSS score: 9.4), has been described as an authentication bypass related to FortiOS single sign-on (SSO). The flaw also affects FortiManager and FortiAnalyzer. The company said it's continuing to investigate if other products, including FortiWeb and FortiSwitch Manager, are impacted by the flaw. "An Authentication Bypass Using an Alternate Path or Channel vulnerability [CWE-288] in FortiOS, FortiManager, FortiAnalyzer may allow an attacker with a FortiCloud account and a registered device to log into other devices registered to other accounts, if FortiCloud SSO authentication is enabled on those devices," Fortinet said in an advisory released Tuesday. It's worth noting that the FortiCloud SSO login feature is not enabled in the default factory settings. It...

Microsoft on Monday issued out-of-band security patches for a high-severity Microsoft Office zero-day vulnerability exploited in attacks. The vulnerability, tracked as CVE-2026-21509 , carries a CVSS score of 7.8 out of 10.0. It has been described as a security feature bypass in Microsoft Office. "Reliance on untrusted inputs in a security decision in Microsoft Office allows an unauthorized attacker to bypass a security feature locally," the tech giant said in an advisory. "This update addresses a vulnerability that bypasses OLE mitigations in Microsoft 365 and Microsoft Office, which protect users from vulnerable COM/OLE controls." Successful exploitation of the flaw relies on an attacker sending a specially crafted Office file and convincing recipients to open it. It also noted that the Preview Pane is not an attack vector. The Windows maker said customers running Office 2021 and later will be automatically protected via a service-side change , but will b...

Cisco has released fresh patches to address what it described as a "critical" security vulnerability impacting multiple Unified Communications (CM) products and Webex Calling Dedicated Instance that it has been actively exploited as a zero-day in the wild. The vulnerability, CVE-2026-20045 (CVSS score: 8.2), could permit an unauthenticated remote attacker to execute arbitrary commands on the underlying operating system of a susceptible device. "This vulnerability is due to improper validation of user-supplied input in HTTP requests," Cisco said in an advisory. "An attacker could exploit this vulnerability by sending a sequence of crafted HTTP requests to the web-based management interface of an affected device. A successful exploit could allow the attacker to obtain user-level access to the underlying operating system and then elevate privileges to root." The critical rating for the flaw is due to the fact that its exploitation could allow for privil...

A threat actor likely aligned with China has been observed targeting critical infrastructure sectors in North America since at least last year. Cisco Talos, which is tracking the activity under the name UAT-8837 , assessed it to be a China-nexus advanced persistent threat (APT) actor with medium confidence based on tactical overlaps with other campaigns mounted by threat actors from the region. The cybersecurity company noted that the threat actor is "primarily tasked with obtaining initial access to high-value organizations," based on the tactics, techniques, and procedures (TTPs) and post-compromise activity observed. "After obtaining initial access — either by successful exploitation of vulnerable servers or by using compromised credentials — UAT-8837 predominantly deploys open-source tools to harvest sensitive information such as credentials, security configurations, and domain and Active Directory (AD) information to create multiple channels of access to their v...

Cisco on Thursday released security updates for a maximum-severity security flaw impacting Cisco AsyncOS Software for Cisco Secure Email Gateway and Cisco Secure Email and Web Manager, nearly a month after the company disclosed that it had been exploited as a zero-day by a China-nexus advanced persistent threat (APT) actor codenamed UAT-9686. The vulnerability, tracked as CVE-2025-20393 (CVSS score: 10.0), is a remote command execution flaw arising as a result of insufficient validation of HTTP requests by the Spam Quarantine feature. Successful exploitation of the defect could permit an attacker to execute arbitrary commands with root privileges on the underlying operating system of an affected appliance. However, for the attack to work, three conditions must be met - The appliance is running a vulnerable release of Cisco AsyncOS Software The appliance is configured with the Spam Quarantine feature The Spam Quarantine feature is exposed to and reachable from the internet L...

The U.S. Cybersecurity and Infrastructure Security Agency (CISA) has warned of active exploitation of a high-severity security flaw impacting Gogs by adding it to its Known Exploited Vulnerabilities ( KEV ) catalog. The vulnerability, tracked as CVE-2025-8110 (CVSS score: 8.7), relates to a case of path traversal in the repository file editor that could result in code execution. "Gogs Path Traversal Vulnerability: Gogs contains a path traversal vulnerability affecting improper Symbolic link handling in the PutContents API that could allow for code execution," CISA said in an advisory. Details of the shortcoming came to light last month when Wiz said it discovered it being exploited in zero-day attacks. The vulnerability essentially bypasses protections put in place for CVE-2024-55947 to achieve code execution by creating a git repository, committing a symbolic link pointing to a sensitive target, and using the PutContents API to write data to the symlink. This, in t...

Chinese-speaking threat actors are suspected to have leveraged a compromised SonicWall VPN appliance as an initial access vector to deploy a VMware ESXi exploit that may have been developed as far back as February 2024. Cybersecurity firm Huntress, which observed the activity in December 2025 and stopped it before it could progress to the final stage, said it may have resulted in a ransomware attack. Most notably, the attack is believed to have exploited three VMware vulnerabilities that were disclosed as zero-days by Broadcom in March 2025: CVE-2025-22224 (CVSS score: 9.3), CVE-2025-22225 (CVSS score: 8.2), and CVE-2025-22226 (CVSS score: 7.1). Successful exploitation of the issue could permit a malicious actor with admin privileges to leak memory from the Virtual Machine Executable (VMX) process or execute code as the VMX process. That same month, the U.S. Cybersecurity and Infrastructure Security Agency (CISA) added the flaws to the Known Exploited Vulnerabilities (KEV) ca...

The Cyber Security Agency of Singapore (CSA) has issued a bulletin warning of a maximum-severity security flaw in SmarterTools SmarterMail email software that could be exploited to achieve remote code execution. The vulnerability, tracked as CVE-2025-52691 , carries a CVSS score of 10.0. It relates to a case of arbitrary file upload that could enable code execution without requiring any authentication. "Successful exploitation of the vulnerability could allow an unauthenticated attacker to upload arbitrary files to any location on the mail server, potentially enabling remote code execution," CSA said. Vulnerabilities of this kind allow the upload of dangerous file types that are automatically processed within an application's environment. This could pave the way for code execution if the uploaded file is interpreted and executed as code, as is the case with PHP files. In a hypothetical attack scenario, a bad actor could weaponize this vulnerability to place malici...

Cyber threats last week showed how attackers no longer need big hacks to cause big damage. They're going after the everyday tools we trust most — firewalls, browser add-ons, and even smart TVs — turning small cracks into serious breaches. The real danger now isn't just one major attack, but hundreds of quiet ones using the software and devices already inside our networks. Each trusted system can become an entry point if it's left unpatched or overlooked. Here's a clear look at the week's biggest risks, from exploited network flaws to new global campaigns and fast-moving vulnerabilities. ⚡ Threat of the Week Flaws in Multiple Network Security Products Come Under Attack — Over the past week, Fortinet , SonicWall , Cisco , and WatchGuard said vulnerabilities in their products have been exploited by threat actors in real-world attacks. Cisco said attacks exploiting CVE-2025-20393, a critical flaw in AsyncOS, have been abused by a China-nexus advanced persistent threat (APT) actor cod...

Cisco has alerted users to a maximum-severity zero-day flaw in Cisco AsyncOS software that has been actively exploited by a China-nexus advanced persistent threat (APT) actor codenamed UAT-9686 in attacks targeting Cisco Secure Email Gateway and Cisco Secure Email and Web Manager. The networking equipment major said it became aware of the intrusion campaign on December 10, 2025, and that it has singled out a "limited subset of appliances" with certain ports open to the internet. It's currently not known how many customers are affected. "This attack allows the threat actors to execute arbitrary commands with root privileges on the underlying operating system of an affected appliance," Cisco said in an advisory. "The ongoing investigation has revealed evidence of a persistence mechanism planted by the threat actors to maintain a degree of control over compromised appliances." The as-yet-unpatched vulnerability is being tracked as CVE-2025-20393 , ...

The threat actor linked to Operation ForumTroll has been attributed to a fresh set of phishing attacks targeting individuals within Russia, according to Kaspersky. The Russian cybersecurity vendor said it detected the new activity in October 2025. The origins of the threat actor are presently unknown. "While the spring cyberattacks focused on organizations, the fall campaign honed in on specific individuals: scholars in the field of political science, international relations, and global economics, working at major Russian universities and research institutions," security researcher Georgy Kucherin said . Operation ForumTroll refers to a series of sophisticated phishing attacks exploiting a then-zero-day vulnerability in Google Chrome (CVE-2025-2783) to deliver the LeetAgent backdoor and a spyware implant known as Dante. The latest attack wave also commences with emails that claimed to be from eLibrary, a Russian scientific electronic library, with the messages sent f...

If you use a smartphone, browse the web, or unzip files on your computer, you are in the crosshairs this week. Hackers are currently exploiting critical flaws in the daily software we all rely on—and in some cases, they started attacking before a fix was even ready. Below, we list the urgent updates you need to install right now to stop these active threats. ⚡ Threat of the Week Apple and Google Release Fixes for Actively Exploited Flaws — Apple released security updates for iOS, iPadOS, macOS, tvOS, watchOS, visionOS, and Safari web browser to address two zero-days that the company said have been exploited in highly targeted attacks. CVE-2025-14174 has been described as a memory corruption issue, while the second, CVE-2025-43529, is a use-after-free bug. They can both be exploited using maliciously crafted web content to execute arbitrary code. CVE-2025-14174 was also addressed by Google in its Chrome browser since it resides in its open-source Almost Native Graphics Layer Engi...

Apple on Friday released security updates for iOS, iPadOS, macOS, tvOS, watchOS, visionOS, and its Safari web browser to address two security flaws that it said have been exploited in the wild, one of which is the same flaw that was patched by Google in Chrome earlier this week. The vulnerabilities are listed below - CVE-2025-43529 (CVSS score: N/A) - A use-after-free vulnerability in WebKit that may lead to arbitrary code execution when processing maliciously crafted web content CVE-2025-14174 (CVSS score: 8.8) - A memory corruption issue in WebKit that may lead to memory corruption when processing maliciously crafted web content Apple said it's aware that the shortcomings "may have been exploited in an extremely sophisticated attack against specific targeted individuals on versions of iOS before iOS 26." It's worth noting that CVE-2025-14174 is the same vulnerability that Google issued patches for in its Chrome browser on December 10, 2025. It's been...

A high-severity unpatched security vulnerability in Gogs has come under active exploitation, with more than 700 compromised instances accessible over the internet, according to new findings from Wiz. The flaw, tracked as CVE-2025-8110 (CVSS score: 8.7), is a case of file overwrite in the file update API of the Go-based self-hosted Git service. A fix for the issue is said to be currently in the works. The company said it accidentally discovered the zero-day flaw in July 2025 while investigating a malware infection on a customer's machine. "Improper symbolic link handling in the PutContents API in Gogs allows local execution of code," according to a description of the vulnerability in CVE.org. The cloud security company said CVE-2025-8110 is a bypass for a previously patched remote code execution flaw ( CVE-2024-55947 , CVSS score: 8.7) that allows an attacker to write a file to an arbitrary path on the server and gain SSH access to the server. CVE-2024-55947 was add...

Google on Wednesday shipped security updates for its Chrome browser to address three security flaws, including one it said has come under active exploitation in the wild. The vulnerability, rated high in severity, is being tracked under the Chromium issue tracker ID " 466192044 ." Unlike other disclosures, Google has opted to keep information about the CVE identifier, the affected component, and the nature of the flaw under wraps. However, a GitHub commit for the Chromium bug ID has revealed that the issue resides in Google's open-source Almost Native Graphics Layer Engine ( ANGLE ) library, with the commit message stating "Metal: Don't use pixelsDepthPitch to size buffers. pixelsDepthPitch is based on GL_UNPACK_IMAGE_HEIGHT, which can be smaller than the image height." This indicates the problem is likely a buffer overflow vulnerability in ANGLE's Metal renderer triggered by improper buffer sizing, which could lead to memory corruption, program cra...

Microsoft closed out 2025 with patches for 56 security flaws in various products across the Windows platform, including one vulnerability that has been actively exploited in the wild. Of the 56 flaws, three are rated Critical, and 53 are rated Important in severity. Two other defects are listed as publicly known at the time of the release. These include 29 privilege escalation, 18 remote code execution, four information disclosure, three denial-of-service, and two spoofing vulnerabilities. In total, Microsoft has addressed a total of 1,275 CVEs in 2025, according to data compiled by Fortra. Tenable's Satnam Narang said 2025 also marks the second consecutive year where the Windows maker has patched over 1,000 CVEs. It's the third time it has done so since Patch Tuesday's inception. The update is in addition to 17 shortcomings the tech giant patched in its Chromium-based Edge browser since the release of the November 2025 Patch Tuesday update . This also consists of a s...

It's been a week of chaos in code and calm in headlines. A bug that broke the internet's favorite framework, hackers chasing AI tools, fake apps stealing cash, and record-breaking cyberattacks — all within days. If you blink, you'll miss how fast the threat map is changing. New flaws are being found, published, and exploited in hours instead of weeks. AI-powered tools meant to help developers are quickly becoming new attack surfaces. Criminal groups are recycling old tricks with fresh disguises — fake apps, fake alerts, and fake trust. Meanwhile, defenders are racing to patch systems, block massive DDoS waves, and uncover spy campaigns hiding quietly inside networks. The fight is constant, the pace relentless. For a deeper look at these stories, plus new cybersecurity tools and upcoming expert webinars, check out the full ThreatsDay Bulletin. ⚡ Threat of the Week Max Severity React Flaw Comes Under Attack — A critical security flaw impacting React Server Components (RSC) has ...

A human rights lawyer from Pakistan's Balochistan province received a suspicious link on WhatsApp from an unknown number, marking the first time a civil society member in the country was targeted by Intellexa's Predator spyware, Amnesty International said in a report. The link, the non-profit organization said, is a "Predator attack attempt based on the technical behaviour of the infection server, and on specific characteristics of the one-time infection link which were consistent with previously observed Predator 1-click links." Pakistan has dismissed the allegations, stating "there is not an iota of truth in it." The findings come from a new joint investigation published in collaboration with Israeli newspaper Haaretz, Greek news site Inside Story, and Swiss tech site Inside IT. It's based on documents and other materials leaked from the company, including internal documents, sales and marketing material, and training videos. Intellexa is the mak...

The U.S. Cybersecurity and Infrastructure Security Agency (CISA) on Thursday released details of a backdoor named BRICKSTORM that has been put to use by state-sponsored threat actors from the People's Republic of China (PRC) to maintain long-term persistence on compromised systems. "BRICKSTORM is a sophisticated backdoor for VMware vSphere and Windows environments," the agency said . "BRICKSTORM enables cyber threat actors to maintain stealthy access and provides capabilities for initiation, persistence, and secure command-and-control." Written in Golang, the custom implant essentially gives bad actors interactive shell access on the system and allows them to browse, upload, download, create, delete, and manipulate files The malware, mainly used in attacks targeting governments and information technology (IT) sectors, also supports multiple protocols, such as HTTPS, WebSockets, and nested Transport Layer Security (TLS), for command-and-control (C2), DNS-o...

Microsoft has silently plugged a security flaw that has been exploited by several threat actors since 2017 as part of the company's November 2025 Patch Tuesday updates , according to ACROS Security's 0patch . The vulnerability in question is CVE-2025-9491 (CVSS score: 7.8/7.0), which has been described as a Windows Shortcut (LNK) file UI misinterpretation vulnerability that could lead to remote code execution. "The specific flaw exists within the handling of .LNK files," according to a description in the NIST National Vulnerability Database (NVD). "Crafted data in an .LNK file can cause hazardous content in the file to be invisible to a user who inspects the file via the Windows-provided user interface. An attacker can leverage this vulnerability to execute code in the context of the current user." In other words, these shortcut files are crafted such that viewing their properties in Windows conceals the malicious commands executed by them out of the u...