Arctic Wolf Labs investigated multiple intrusions in June that began by exploiting an authentication bypass in Palo Alto Networks PAN-OS and ended in Qilin ransomware. CVE-2026-0257 affects the portal and gateway components and lets an unauthenticated remote attacker establish a VPN session without valid credentials, but only where authentication override cookies are enabled alongside specific certificate configurations. That narrow precondition makes it easy to assume you are unaffected without checking. The flaw is patched. Because it grants VPN access rather than code execution, the intrusions look like ordinary remote logins at the start, which delays detection until ransomware is deployed.
BeyondTrust has patched two critical flaws in its Remote Support and Privileged Remote Access products that let an unauthenticated, network-positioned attacker bypass authentication and reach the appliance, including accounts with elevated privileges. The bugs, CVE-2026-40138 and CVE-2026-40139, both rated 9.2, sit in the authentication subsystem and depend on a specific authentication configuration being enabled. Cloud-hosted customers were patched automatically in April, but self-hosted deployments on version 25.3.2 or earlier need to update themselves. BeyondTrust has not reported exploitation, but its remote-support products have a history of being attacked, including flaws used to breach the US Treasury and to deploy ransomware, so internet-facing appliances should be patched quickly.
Attackers have started probing a critical flaw in Gitea's official Docker images, the self-hosted Git service used by many development teams. The images shipped a configuration that trusted the X-WEBAUTH-USER header from any source address, so with reverse-proxy login enabled, anyone who could reach the port could send that header and be authenticated as any user, no password required. Tracked as CVE-2026-20896 and rated 9.8, it was fixed in version 1.26.3 late last month, which removes the wildcard and makes reverse-proxy authentication opt-in. Sysdig reported the first exploitation attempt 13 days after disclosure, so far just reconnaissance, against some of the roughly 6,200 internet-facing Gitea instances.
The curl project shipped its largest-ever security release, version 8.21.0, fixing 18 vulnerabilities, among them a flaw that had gone unnoticed for 25 years. That bug (CVE-2026-8932) lets an application reuse an existing connection even after its client certificate or key changed, allowing an authentication bypass; it affects software built on the libcurl library rather than the command-line tool. Other fixes address credential confusion, memory-corruption bugs, and improper host validation. Most are rated medium or low, but libcurl is embedded in an enormous range of products, from IoT devices to CI/CD pipelines and cars, so the practical reach is large and easy to overlook.
Quest KACE has a year-old maximum-severity authentication bypass (CVE-2025-32975, CVSS 10.0). Hunt.io researchers now report that an attacker exploited an unpatched KACE appliance at a Boston-area managed services provider called HIQ - then left their entire toolkit on a publicly accessible server with directory listing turned on. The exfiltrated 512 MB MariaDB dump turned out to contain the full appliance-managed endpoint list for over 60 named client organizations spanning law enforcement, government, healthcare, education, and private companies. None of those 60-plus organizations had any KACE relationship of their own - they were just customers of the MSP that ran it unpatched.
Progress Software released emergency patches Sunday for two MOVEit Automation flaws. The worst, CVE-2026-4670 (CVSS 9.8), lets remote attackers reach the management interface without logging in - and from there take administrative control. Airbus researchers disclosed both flaws privately and Progress hasn't seen exploitation in the wild, but the comparison with MOVEit's history is uncomfortable: the Cl0p ransomware gang exploited MOVEit Transfer in 2023 to steal data from 2,100 organizations and 62 million individuals. Shodan shows 1,400+ MOVEit Automation instances exposed online, including a dozen linked to US local and state government agencies.
SonicWall released emergency firmware updates for Gen 6, Gen 7, and Gen 8 firewalls after CrowdStrike's research team disclosed three SonicOS flaws on April 29. The worst is CVE-2026-0204 (CVSS 8.0), a weak authentication bug in the management interface that lets an attacker on an adjacent network reach management functions without logging in - and from there change firewall rules, disable security protections, or open new holes. The other two are post-authentication: CVE-2026-0205 is a path traversal that breaks out of restricted directories, and CVE-2026-0206 is a buffer overflow that crashes the firewall. No public exploits yet.
cPanel disclosed a critical authentication bypass on Monday affecting every cPanel and WHM version - including end-of-life builds. CVSS 9.8. The bug let unauthenticated attackers log in as administrators by abusing how the cPanel session daemon writes session files during login. Hosting providers including Namecheap, KnownHost, hosting.com, HostPapa, and InMotion took cPanel and WHM offline globally for hours while patches deployed. Researchers at watchTowr published a working proof-of-concept on April 29. KnownHost reports possible targeted exploitation as early as February 23, 2026 - more than two months before disclosure.
Microsoft released out-of-band security updates for a critical ASP.NET Core Data Protection flaw that lets unauthenticated attackers forge authentication cookies and escalate to SYSTEM privileges. The bug (CVE-2026-40372) is a regression introduced in the April 2026 Patch Tuesday: the Microsoft.AspNetCore.DataProtection 10.0.0 through 10.0.6 NuGet packages compute the HMAC validation tag (the cryptographic signature that proves a cookie has not been tampered with) over the wrong bytes of the payload and then discard the hash in some cases. The broken check means attackers can forge payloads that pass DataProtection's authenticity checks and decrypt previously-protected data in auth cookies, antiforgery tokens, TempData, and OIDC state. Microsoft noticed the flaw only after users reported decryption failures in their apps after installing the .NET 10.0.6 update. Critical operational detail: updating to 10.0.7 stops future forgeries, but any tokens an attacker already got the app to legitimately sign during the vulnerable window (session refresh tokens, API keys, password reset links) remain valid forever unless you rotate the DataProtection key ring. Patching alone is not enough.
A CVSS 9.8 authentication bypass in nginx-ui, the popular open-source web management interface for Nginx servers, is being actively exploited in the wild. The flaw, codenamed MCPwn by Pluto Security, exists because the /mcp_message endpoint added for Model Context Protocol (AI integration) support only checks IP whitelisting - and the default whitelist is empty, meaning it allows all connections. One unauthenticated HTTP POST request lets an attacker invoke all MCP tools: rewrite Nginx config files, reload the server, intercept all traffic, and harvest admin credentials. Attackers chain it with CVE-2026-27944 (exposed encryption keys via the backup API) to extract the node_secret needed for full MCP access. Recorded Future flagged active exploitation and assigned a risk score of 94/100. Shodan shows 2,600 publicly exposed instances, mostly in China, the US, Indonesia, and Germany. Pluto Security's key lesson: AI integration endpoints expose the same capabilities as the core application but often skip its security controls.