The original 2011 Microsoft certificates that underpin UEFI Secure Boot begin expiring in late June 2026, and organizations that have not rolled out the replacement 2023 certificates risk a slow erosion of boot-level security. Devices will keep starting normally, but once the old certificate authorities lapse they stop receiving Secure Boot updates for pre-boot components, leaving them more exposed to bootkits, and future bootloaders signed only with the new keys may fail to verify. Most consumer Windows PCs receive the 2023 certificates automatically through Windows Update, but Windows Server and many self-managed or older fleets need manual action. A second certificate that signs the Windows bootloader expires in October.
Attackers are mass-exploiting a flaw in Gravity SMTP, a WordPress email plugin installed on about 100,000 sites, to harvest credentials without any login. The bug (CVE-2026-4020) leaves a REST API endpoint with a permission check that always passes, so a single unauthenticated request returns a 365 KB system report containing API keys, secrets, and OAuth tokens for connected email services like Amazon SES, Mailjet, and Zoho, plus detailed software-stack information. Wordfence has blocked more than 17 million attempts, with activity spiking around June 6 and 7. A patch shipped in version 2.1.5, but updating does not revoke keys attackers may have already grabbed.
A critical Splunk Enterprise flaw disclosed earlier this month is now being exploited in the wild, and CISA has added it to its known-exploited list with a June 21 federal patch deadline. The bug (CVE-2026-20253, rated 9.8) is a missing-authentication issue in a PostgreSQL sidecar service: an unauthenticated, network-reachable attacker can create or truncate arbitrary files on the Splunk host, which can cascade into log corruption, broken monitoring, and remote code execution. Both Splunk and Resecurity have confirmed active exploitation, and a public proof-of-concept and Nuclei template exist. Because Splunk underpins many SOC and SIEM operations, a compromise can blind defenders.
Researchers at Paradigm Shift published usbliter8, a working exploit that runs unauthorized code inside the SecureROM of Apple's A12 and A13 chips, the boot code burned into the silicon of devices from the iPhone XS through the iPhone 11, plus the S4 and S5 Apple Watch chips. Because the flaw lives in immutable hardware, no software update can fix it, so affected devices stay vulnerable for life. The catch is that it is not remote: an attacker needs physical possession of the device, must put it in DFU mode, and connect it to a special USB board, after which the exploit runs in under two seconds. It succeeds 2019's checkm8.
F5 has issued out-of-band patches for two critical flaws in NGINX, the web server and reverse proxy that runs a large share of the internet. CVE-2026-42530 (a use-after-free in the HTTP/3 module) and CVE-2026-42055 (a heap overflow in the HTTP/2 proxy and gRPC modules), both rated 9.2, let a remote, unauthenticated attacker corrupt memory in an NGINX worker, crashing it for a denial of service and, where address-space randomization is disabled or bypassed, potentially running code. They affect non-default configurations across NGINX Open Source, Plus, Gateway Fabric, and Instance Manager. F5 has not seen exploitation yet, but its products are frequent attacker targets.
Cisco has patched serious flaws in Identity Services Engine (ISE), the platform many organizations use to control who and what connects to their network. The most severe is a critical remote-code-execution bug that can give an attacker root-level control of the appliance. A second flaw, CVE-2026-20190, is an unauthenticated information-disclosure issue caused by weak authorization checks, letting a remote attacker pull sensitive data, including hashed credentials, that could fuel follow-on attacks and lateral movement. All versions of ISE and ISE-PIC are affected, though which flaws apply varies by release. Cisco has not reported active exploitation, but ISE sits at the heart of network access control.
A critical flaw in the Joomla Content Editor (JCE), one of the most widely used editor extensions for the Joomla CMS, is being actively exploited to take over websites. The bug (CVE-2026-48907, rated a perfect 10) is an access-control failure that lets an unauthenticated attacker create editor profiles and then upload and run arbitrary PHP code, leading to full server compromise. CISA added it to its known-exploited list and ordered federal agencies to patch by June 19. Working exploit code is public and attacks are automated, so even sites with no public registration are at risk. Patching closes the hole but does not remove anything attackers already planted.
CISA has added a LiteSpeed cPanel plugin flaw to its known-exploited list and given federal agencies until June 18 to patch. The bug (CVE-2026-54420, rated 8.5) lets a user who already has FTP or web-shell access on a shared hosting server escalate to root by abusing how the plugin follows symbolic links, on servers running CloudLinux or CageFS. On multi-tenant hosting that turns one compromised account into full control of the whole server and every site on it. Namecheap reported it after spotting suspicious activity, and LiteSpeed flagged active exploitation in early June. The fix is LiteSpeed WHM Plugin 5.3.2.1 with cPanel plugin 2.4.8.
Threat-intelligence firm Defused reports that attackers are now exploiting three critical flaws in Fortinet's FortiSandbox, the appliance other Fortinet products rely on to judge whether files are malicious. Two (CVE-2026-39813, a JRPC API path traversal that bypasses authentication, and CVE-2026-39808, an unauthenticated command-injection that runs code as root) were patched in April; the third (CVE-2026-25089) only last week. All are unauthenticated and rated critical. Compromising a sandbox is especially dangerous because attackers can make it wave real malware through as clean. Notably, the exploit for one flaw appears to have been generated with AI and is likely faulty, yet attackers are trying it anyway.
Palo Alto's Unit 42 disclosed a flaw, nicknamed Pickle in the Middle, in Google Cloud's Vertex AI SDK for Python that let an attacker with no access to a victim's project hijack their machine-learning model uploads and run code across tenant boundaries. When a model was uploaded without a custom staging bucket, the SDK generated a predictable storage bucket name from the project ID and region and failed to verify ownership, so an attacker could pre-create that bucket, receive the victim's model, and swap in a malicious one that executes on deployment. Google fully fixed it in SDK version 1.148.0 in April; Unit 42 saw no exploitation in the wild.
TrustStrike Labs