Loki Intelligence — Security Briefs · Published
Daily Security Brief: Atlassian Critical Flaw, Rejetto HFS Scanning, Exchange Update
Today's picture centers on self-hosted infrastructure: a critical Atlassian Data Center flaw, active scanning for Rejetto HFS, and an out-of-band Exchange fix. Teams should prioritize patching internet-exposed and self-hosted systems, and review how AI agents and MCP servers are given access to data and tools.
Signal 01 · BleepingComputer
Atlassian warns of critical file-access flaw in Jira, Confluence
Atlassian has warned customers about a critical vulnerability, CVE-2026-21589, that allows arbitrary file access in several self-hosted Data Center products, including Confluence, Jira and Bitbucket.
Why it matters: Teams running self-hosted Atlassian Data Center should identify affected instances, apply the vendor's guidance promptly and limit exposure of these systems to the internet.
Source: BleepingComputer
Signal 02 · The Hacker News
Welcome to the Jungle: What We Found Inside 15,465 Public MCP Servers
A research write-up examines 15,465 publicly reachable MCP (Model Context Protocol) servers, the standard many teams use to connect AI models, agents and IDEs to tools and data.
Why it matters: Anyone running or consuming MCP servers should inventory them, restrict what they can reach and treat them as part of the attack surface rather than as trusted developer tooling.
Source: The Hacker News
Signal 03 · BleepingComputer
Rejetto HFS servers now actively scanned for critical RCE flaw
Attackers are reportedly scanning for Rejetto HFS servers affected by CVE-2026-61500, a weak signing key issue that can lead to session forgery, account takeover and remote code execution.
Why it matters: Organizations running HFS should update or remove exposed instances now and review them for signs of unauthorized sessions or account changes.
Source: BleepingComputer
Signal 04 · The Hacker News
Microsoft Exchange Flaw Lets Authenticated Attackers Read Other Users' Mailboxes
Microsoft released out-of-band updates for CVE-2026-96940, a high-severity Exchange Server flaw rated 8.8 on CVSS that could allow privilege escalation under certain conditions and let authenticated users read other mailboxes.
Why it matters: Exchange administrators should deploy the out-of-band updates quickly and review mailbox access and audit logging for unexpected activity.
Source: The Hacker News
Signal 05 · The Hacker News
⚡ Weekly Recap: NetScaler and FortiMail 0-Days, AI Coding Leaks, Spectre v2 and Ransomware Arrests
The weekly recap covers NetScaler and FortiMail zero-days, AI coding leaks, Spectre v2 and ransomware arrests, noting that many threats exploit small, easily overlooked weaknesses.
Why it matters: Routine hygiene, such as checking exposed devices, public repositories and form or email handling, remains a practical way to reduce this kind of exposure.
Source: The Hacker News
Signal 06 · The Hacker News
Apple Plans Tighter macOS Full Disk Access Controls Over AI Agent Data Access
Apple has announced plans to tighten controls around the macOS Full Disk Access setting because of security risks linked to AI agents.
Why it matters: Teams building or deploying AI agents on macOS should apply least privilege and avoid depending on broad disk access, since platform restrictions may change.
Source: The Hacker News
Signal 07 · BleepingComputer
Google halts open-source bug bounty program amid AI spam surge
Google has suspended submissions to its Open Source Software Vulnerability Rewards Program after being flooded with AI-generated reports.
Why it matters: Open-source maintainers and security teams should expect more low-quality automated reports and ensure that findings get human validation before they are triaged or filed.
Source: BleepingComputer
Brief sources
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Relevant Loki services: Orvyn — AI agent security private preview and SKYEN web & API pentesting.