Attackers are exploiting a third Citrix NetScaler zero-day disclosed in less than a week, using a single request to knock SAML-enabled appliances offline and disrupt services behind them. Citrix released a patch, while Microsoft issued emergency Exchange updates for a separate flaw that lets authenticated attackers read colleagues’ mailboxes; Microsoft reported no evidence of exploitation.
Older flaws are still giving attackers a way in: Warlock ransomware hit at least four organizations in two months through unpatched SharePoint systems, including a water utility and a telecom provider. Google’s threat intelligence team recorded 141 exploited vulnerabilities from January through August, already exceeding its total for all of 2025.
AI is helping find real flaws and flooding security teams with bad reports. Google’s internal PageBreak agent found more than 500 verified cross-site scripting flaws, but a surge in mostly invalid automated submissions led the company to stop accepting product vulnerability reports under its open-source bounty program.
Google announced six Advanced Protection enhancements for Android 17 to counter malicious apps, browser exploits and unauthorized access, including restrictions on accessibility permissions and disabling WebGPU. Four features apply generally to Android 17 devices, while USB Protection and Failed Authentication Lock require selected devices. Optional Intrusion Logging preserves encrypted records remotely for compromise investigations and must be enabled separately.
Atlassian patched CVE-2026-21589, a critical file-access flaw affecting eight products, including Jira, Confluence and Bitbucket Data Center. The flaw, rated CVSS 9.3, lets unauthenticated attackers access files in an application’s web root if they know the exact filename and path; it does not allow directory listing. Atlassian said affected Cloud products were already patched and its investigation found no evidence of exploitation.
Dell fixed a critical path traversal flaw in System Update versions before 2.3.0.0 that can let unauthenticated remote attackers execute code as root on PowerEdge servers. Tracked as CVE-2026-86360, the flaw has a CVSS score of 9.6. Version 2.3.0.0 also fixes four other vulnerabilities; Dell has not reported active exploitation of any of the flaws.
A ClickFix attack uses compromised websites to cache malicious scripts disguised as PNG files, then tricks Windows users into running them. Microsoft said the technique bypasses the Windows Run dialog’s roughly 260-character limit by executing content already on the device. The infection chain loads .NET assemblies into memory and injects code into the legitimate timeout.exe process to target browser and device credentials.
Attackers are exploiting CVE-2026-88779, a denial-of-service zero-day affecting Citrix NetScaler ADC and Gateway instances with SAML enabled. A single specially crafted request can knock an appliance offline and disrupt access to services behind it. Citrix released a patch, and CISA added the flaw to its known exploited vulnerabilities catalog Sunday.
Microsoft released emergency updates for Exchange Server flaw CVE-2026-96940, which lets authenticated attackers read other users’ emails and attachments within the same organization. The vulnerability affects Subscription Edition RTM, Exchange Server 2016 CU23, and Exchange Server 2019 CU14 and CU15; Microsoft has already fixed Exchange Online. There is no evidence of exploitation in the wild.
Fortbridge researchers demonstrated code execution on two tested WordPress server stacks through crafted HEIC uploads that exploit a libheif decoder flaw. The chain requires a logged-in user with upload_files permission and uses memory leaked through generated JPEGs. The flaw, GHSA-x8r2-mggj-j6wr, affects libheif 1.18.0 through 1.23.2 and is fixed in 1.23.3; the report identified no active exploitation campaign.
Apple plans to tighten macOS Full Disk Access controls to require explicit user action, citing risks that AI agents could expose files, mail, messages and browsing history without users fully understanding the access granted. The company has not announced a rollout date. The move follows a report that Meta’s Muse agent accessed a journalist’s private iMessages after receiving Full Disk Access.
Jamf Threat Labs found CloudSyncD, a macOS backdoor delivered through a fake Zoom installer that tricks users into supplying their account passwords. The malware hides the captured password in a settings file, using invisible Unicode characters to mark its location, and uses it to run an embedded payload with sudo. The backdoor contacts live command-and-control domains and can download and run additional programs.