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Paperclip AI · Gogs · Windows hosts with low-privilege user sessions

DAILY THREAT INTELLIGENCE BRIEFING Date: 2026-06-20 Prepared for: SOC Analysts | Incident Responders | Vulnerability Management | Security Leadership

EXECUTIVE SUMMARY

Today’s most significant new developments are a Metasploit module for an unauthenticated RCE chain in Paperclip AI (CVE-2026-41679), active exploitation of a Gravity SMTP WordPress plugin information disclosure vulnerability affecting 100,000 sites, a new NTLM relay-to-self privilege escalation technique now weaponized in Metasploit, and a Gogs authentication bypass via unvalidated reverse proxy headers disclosed by Tenable. Unit 42 has published guidance on large-scale credential attacks targeting security vendor devices. The Klue OAuth breach has expanded with the Icarus extortion group claiming responsibility.

CRITICAL VULNERABILITIES

NEW

CVE-2026-41679 (Paperclip AI)

  • Affected products: Paperclip AI (all network-accessible instances running in authenticated mode with default configuration)
  • Severity: Not yet CVSS-scored in available data
  • EPSS: Not yet scored
  • Technical detail: An unauthenticated attacker can achieve full remote code execution on any network-accessible Paperclip AI instance via a chain of six sequential API calls. No credentials are required. A Metasploit module (linux/http/paperclipai_unauth_rce_cve_2026_41679) was published on 2026-06-19, significantly lowering the barrier to exploitation. The attack is fully automated and requires only network reachability to the target service.
  • Exploitation status: No confirmed in-the-wild exploitation reported, but public Metasploit module availability makes exploitation highly likely in the near term.
  • Remediation: Restrict network access to Paperclip AI instances immediately. Apply vendor patches when available. Monitor for anomalous API call sequences matching the six-step chain. Treat as emergency priority given weaponized public exploit.

Gogs Authentication Bypass (Tenable TRA-2026-50)

  • Affected products: Gogs (all versions with ENABLE_REVERSE_PROXY_AUTHENTICATION enabled)
  • Severity: Critical (CVSS not yet assigned; BSI advisory WID-SEC-2026-2013 rated kritisch)
  • EPSS: Not yet scored
  • Technical detail: When reverse proxy authentication is enabled, Gogs accepts the X-WEBAUTH-USER header (or any configured equivalent) directly from client requests without verifying the request originated from a trusted reverse proxy. Any remote attacker who can reach the Gogs service directly can forge this header to impersonate any existing user, including administrators, or trigger automatic account creation. This completely bypasses authentication. Gogs is widely used as a self-hosted Git service in enterprise and development environments, including in European organizations.
  • Exploitation status: No confirmed in-the-wild exploitation. Public technical disclosure by Tenable on 2026-06-19 increases exploitation probability.
  • Remediation: Disable ENABLE_REVERSE_PROXY_AUTHENTICATION if not strictly required. If required, enforce network-level controls ensuring only trusted reverse proxy IPs can reach the Gogs service. Apply vendor patches when released. Audit Gogs access logs for unexpected header-based authentication events.

NTLM Relay to Self — Windows Local Privilege Escalation

  • Affected products: Windows hosts with low-privilege user sessions; Domain Controller LDAP service
  • Severity: High (no CVE assigned in available data; technique-based)
  • EPSS: Not applicable
  • Technical detail: A new Metasploit module (windows/local/ntlm_relay_2_self) automates the NTLMRelay2Self attack chain. Starting from a low-privilege session, the module coerces the local machine account to authenticate via OpenEncryptedFileRaw (WebDAV), relays the resulting NTLM authentication to a Domain Controller’s LDAP service, writes Shadow Credentials to the machine account, and obtains a Kerberos service ticket as Administrator via S4U2Proxy, enabling PsExec back to the local host for SYSTEM access. This is a fully weaponized post-exploitation technique requiring only a low-privilege foothold.
  • Exploitation status: Weaponized in Metasploit as of 2026-06-19. No confirmed in-the-wild exploitation reported, but the technique is well-understood and now trivially accessible.
  • Remediation: Enable LDAP signing and channel binding on Domain Controllers to block NTLM relay to LDAP. Disable WebDAV client service on workstations where not required. Monitor for Shadow Credential writes to machine accounts (Event ID 4742 with msDS-KeyCredentialLink changes). Apply Microsoft mitigations for NTLM relay as per prior MSRC guidance.

Gravity SMTP WordPress Plugin — Unauthenticated Information Disclosure

  • Affected products: Gravity SMTP WordPress plugin (active on approximately 100,000 sites)
  • Severity: Not yet CVSS-scored in available data
  • EPSS: Not yet scored
  • Technical detail: An unauthenticated information disclosure vulnerability in the Gravity SMTP plugin is being actively exploited in the wild. Specific technical details on the exposed data type are not fully available in current reporting, but the unauthenticated nature of the flaw and active exploitation indicate attackers are harvesting sensitive configuration or credential data from affected WordPress installations. Given the plugin’s function in handling email delivery, exposed SMTP credentials or API keys are a likely target.
  • Exploitation status: Actively exploited in the wild as of 2026-06-19.
  • Remediation: Update Gravity SMTP to the latest patched version immediately. Rotate any SMTP credentials, API keys, or email service tokens configured within the plugin. Review WordPress access logs for exploitation attempts. Consider temporarily disabling the plugin if patching is not immediately possible.

ONGOING

  • CVE-2026-20253 (Splunk Enterprise): Actively exploited; CISA KEV deadline was 2026-06-21 — verify patch applied today.
  • CVE-2026-12569 (PTC Windchill / FlexPLM): BSI WID-SEC-2026-1991 updated 2026-06-19; still marked UNGEPATCHT; restrict network access.
  • CVE-2026-42530 and related (NGINX): Out-of-band patches available; apply immediately; disable HTTP/3 if not required.
  • CVE-2026-12045 through CVE-2026-12048 (pgAdmin 4): Upgrade to 9.16; restrict to trusted networks.
  • CVE-2026-54130 (Microsoft 365 Copilot): Monitor MSRC for patch; review Copilot access logs.
  • CVE-2026-47647 (Microsoft Dynamics 365): Monitor MSRC for patch; audit privilege assignments.
  • CVE-2026-20262 (Cisco Catalyst SD-WAN Manager): Actively exploited; CISA KEV deadline 2026-06-29; patch immediately.
  • CVE-2026-42271 (LiteLLM): CISA KEV deadline 2026-06-22; upgrade to v1.83.7-stable.
  • CVE-2026-0257 (Palo Alto PAN-OS GlobalProtect): Actively exploited; apply PAN-OS patches.
  • CVE-2026-5027 (Langflow): Actively exploited; isolate from internet.
  • CVE-2026-50751 (Check Point Security Gateway): Actively exploited; apply hotfix sk185033.

EUROPEAN ADVISORIES

BSI published a significant volume of new and updated advisories on 2026-06-19. New advisories of note:

WID-SEC-2026-2013 (Gogs): Covered in Critical Vulnerabilities. Multiple flaws including authentication bypass, RCE, privilege escalation, XSS, and DoS. Rated kritisch.

WID-SEC-2026-2014 (Webmin): New high-severity advisory covering information disclosure, spoofing, and security bypass vulnerabilities in Webmin. Webmin is widely used for Linux server administration in enterprise and hosting environments. Apply available Webmin updates and restrict administrative interface access to trusted networks.

WID-SEC-2026-2012 (HAProxy): New high-severity advisory covering file manipulation and denial-of-service vulnerabilities in HAProxy. HAProxy is a critical load balancing component in many European enterprise and cloud environments. Apply vendor patches promptly.

WID-SEC-2026-2011 (ffmpeg): New high-severity advisory for a remote code execution and DoS vulnerability in ffmpeg. Relevant to media processing pipelines and any application embedding ffmpeg libraries. Apply upstream patches.

WID-SEC-2026-2009 (Google Cloud Platform / GKE containerd): New high-severity advisory marked UNGEPATCHT covering RCE, security bypass, data manipulation, information disclosure, and DoS in GKE containerd. No patch currently available. Organizations using GKE should monitor Google Cloud security bulletins and apply compensating controls.

WID-SEC-2026-2005 (pgAdmin): Covered in Critical Vulnerabilities (yesterday’s report); upgrade to pgAdmin 4 version 9.16.

WID-SEC-2026-2004 (Node.js): New high-severity advisory covering security bypass, data manipulation, information disclosure, and DoS in Node.js. Apply current Node.js LTS security updates.

Updated advisories for Splunk Enterprise (WID-SEC-2026-1877), Drupal Core (WID-SEC-2026-2002), GNU libc (WID-SEC-2026-1190), strongSwan (WID-SEC-2026-1832 and WID-SEC-2026-1247), IBM WebSphere Application Server (WID-SEC-2026-1762), GnuTLS (WID-SEC-2026-1312), Linux Kernel (multiple), OpenSSL (WID-SEC-2026-0234), and Mozilla Firefox/Thunderbird (WID-SEC-2026-1959) were refreshed; apply vendor patches per prior guidance.

ACTIVE THREATS AND CAMPAIGNS

NEW — Large-Scale Credential Attacks Targeting Security Vendor Devices (Unit 42) Unit 42 published a threat brief on 2026-06-20 documenting large-scale credential attack campaigns specifically targeting security vendors’ network devices. The brief provides mitigation guidance focused on credential hygiene, MFA enforcement, and device hardening. This aligns with the ongoing FortiBleed campaign. Organizations should review authentication logs on all perimeter security devices for credential stuffing or brute-force patterns and enforce MFA universally on administrative interfaces.

STATUS CHANGE — Klue OAuth Breach: Icarus Group Claims Responsibility The Icarus extortion group has publicly claimed the Klue breach, and the victim list has expanded beyond initial reporting. Attackers abused OAuth tokens to access connected Salesforce environments. Organizations that used the Klue Battlecards Salesforce integration should treat their Salesforce environments as potentially compromised, audit OAuth grants, and review data access logs from June 11, 2026 onward.

ONGOING — FortiBleed: CISA and NCSC formal advisories active; 74,000+ devices affected; rotate credentials and enforce MFA on all Fortinet devices. ONGOING — Gentlemen RaaS / GentleKiller: EDR killer suite actively distributed to affiliates; verify EDR tamper protection is enabled. ONGOING — DragonForce Ransomware / Backdoor.Turn: C2 via Microsoft Teams relay; review Teams relay traffic for anomalous patterns. ONGOING — SocGholish: Operation Endgame disrupted infrastructure; scan WordPress deployments for residual injections.

SECURITY NEWS AND CONTEXT

AutoJack (Microsoft Research): Microsoft researchers detailed an exploit chain allowing a malicious web page to hijack an AI browsing agent and achieve host-level code execution via a privileged local service, with no user interaction beyond initial page load. Organizations deploying AI browsing agents should assess exposure.

usbliter8 (Apple A12/A13 SecureROM): Researchers published a working exploit for an unpatchable SecureROM vulnerability in Apple A12 and A13 chips. The attack requires physical USB access; remote exploitation is not possible. Enterprise impact is limited but relevant for high-security device management policies.

VS Code Extension Persistence: A new Metasploit persistence module installs a malicious VS Code extension to maintain access across developer workstation sessions. Relevant to organizations where developers have local admin rights.

RECOMMENDED ACTIONS

  1. Restrict network access to Paperclip AI instances immediately and monitor for exploitation of CVE-2026-41679; apply vendor patches when available.
  2. Disable or network-isolate Gogs reverse proxy authentication (ENABLE_REVERSE_PROXY_AUTHENTICATION) until patched; audit access logs for header-forgery attempts.
  3. Enable LDAP signing and channel binding on Domain Controllers and disable WebDAV client on workstations to block the NTLM relay-to-self attack chain.
  4. Update Gravity SMTP WordPress plugin immediately; rotate all SMTP credentials and API keys configured in the plugin.
  5. Apply BSI-flagged patches for Webmin, HAProxy, ffmpeg, and Node.js; restrict Webmin administrative access to trusted networks.
  6. Monitor Google Cloud security bulletins for GKE containerd patches (WID-SEC-2026-2009 currently unpatched); apply compensating controls.
  7. Review Salesforce OAuth grants and audit access logs from June 11 onward if Klue Battlecards integration was in use.
  8. Audit developer workstations for unauthorized VS Code extensions as a new persistence vector now weaponized in Metasploit.
  9. Verify Splunk Enterprise patch is applied — CISA KEV deadline is 2026-06-21.
  10. Continue remediation of previously reported items: CVE-2026-20262 (Cisco SD-WAN, KEV deadline 2026-06-29), CVE-2026-42271 (LiteLLM, KEV deadline 2026-06-22), CVE-2026-42530 (NGINX), CVE-2026-12045 through CVE-2026-12048 (pgAdmin 4), CVE-2026-0257 (PAN-OS), CVE-2026-5027 (Langflow), CVE-2026-50751 (Check Point).