Vulnerabilities Atlassian, Splunk Patch Critical Vulnerabilities Splunk patched an OS command injection in AI Toolkit, while Atlassian fixed dozens of flaws in third-party dependencies. By Ionut Arghire | June 18, 2026 (6:59 AM ET) Flipboard Reddit Whatsapp Whatsapp Email Atlassian and Splunk on Wednesday announced patches for multiple vulnerabilities in their products, including critical-severity flaws. Splunk resolved a critical issue in AI Toolkit that could allow authenticated attackers with admin roles to execute arbitrary OS commands on the host the Splunk Enterprise instance runs on. “The vulnerability is possible because of an unsafe shell execution pattern in the btool configuration helper, which constructs OS command strings from dynamic parameters without disabling shell interpretation,” Splunk explains. Tracked as CVE-2026-20266 (CVSS score of 9.1), the security defect was addressed in Splunk AI Toolkit version 5.7.4. If upgrading is not possible, Splunk recommends uninstalling the AI Toolkit as a mitigation. The update also addresses CVE-2026-20265, a medium-severity information disclosure bug caused by an insecure default domain allowlist. An attacker holding the admin or power role could cause the AI Toolkit to make outbound HTTP requests to attacker-controlled servers, leading to data exfiltration. Atlassian published 100 security bulletins that address dozens of security defects across Bamboo Data Center and Server, Bitbucket Data Center and Server, Confluence Data Center and Server, Crowd Data Center and Server, Fisheye/Crucible, Jira Data Center and Server, and Jira Service Management Data Center and Server. Advertisement. Scroll to continue reading. All the weaknesses resolved with the fresh security updates appear to affect third-party dependencies used in Atlassian’s products. These include critical-severity issues in Axios (CVE-2026-42043, CVE-2026-40175, and CVE-2026-42264), Apache Tomcat (CVE-2026-41293, CVE-2026-43512, CVE-2026-41293, CVE-2026-43515, and CVE-2026-43515), and Netty (CVE-2026-42584). Users are advised to update to a patched version of the affected Atlassian products as soon as possible. Related: Critical Command Execution Vulnerability Patched in Cisco ISE Related: F5 Patches Critical, High-Severity NGINX Vulnerabilities Related: Microsoft Working on Patch for ‘RoguePlanet’ Zero-Day Related: 3 Recently Patched Fortinet FortiSandbox Vulnerabilities in Hacker Crosshairs Written By Ionut Arghire Ionut Arghire is an international correspondent for SecurityWeek. Daily Briefing Newsletter Subscribe to the SecurityWeek Email Briefing for the latest cybersecurity threats, trends, and expert insights. 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Webinar: How Modern Breaches Bypass MFA and Evade Detection June 17, 2026 Today’s attackers are no longer breaking in — they’re logging in. Join this live webinar as we break down the modern identity attack chain and examine how recent breaches exploited weaknesses in authentication, identity verification, and access management processes. Register Webinar: Modern Exposure Validation in the AI Era June 24, 2026 AI has accelerated both sides of the fight. Adversaries are weaponizing vulnerabilities faster, while defenders are racing to ship detections and configurations. Join this live webinar as we explore how to prove your controls actually hold against new threats, map your security maturity, and unite breach simulation with automated pentesting into a single, coordinated program. Register People on the Move Jonathan Trull has joined Oracle as Global Head of Cyber Defense. Plaid has appointed Sean Cassidy as Chief Information Security Officer. Ann Barron-DiCamillo has been named Executive Vice President and Global Chief Information Security Officer at U.S. Bank. More People On The Move Expert Insights After AI Reaches Production: 12 Ways Security Teams Can Take Control Security teams need more than visibility into AI applications, they need a repeatable framework for monitoring, investigating, and defending them in production. (Joshua Goldfarb) Everybody Is Vibe Coding But Nobody Told the Security Team AI-driven development is not something organizations can or should block. But it must be governed. (Danelle Au) The Zero-Knowledge Threat Actor and the End of Responsible Disclosure AI can help attackers generate malware, create malicious payloads, bypass simple security checks, and convert vague malicious intent into functional code. (Etay Maor) Raising the Cybersecurity Stakes: Ante up for the Agentic Era CISOs are now facing machine-speed attacks and asking, “How do I agent?” The industry must provide remediation at scale. (Nadir Izrael) Caught Off Guard: Securing AI After It Hits Production As enterprises rush AI projects into production, security teams are increasingly being forced into reactive mode. (Joshua Goldfarb) Flipboard Reddit Whatsapp Whatsapp Email