Cyber Threat Brief — June 28 2026

⚠️ This report is AI-generated. Always validate findings.

1. Turla STOCKSTAY Backdoor — Ukraine Gov/Military Espionage

TL;DR: GTIG disclosed a previously undocumented .NET backdoor (STOCKSTAY) used by Turla against Ukrainian government/military since late 2022, with full IOC set including file hashes, C2 WebSocket URLs, and phishing infrastructure.

What’s New:

  • GTIG blog published June 26 with complete technical analysis and IOCs
  • Multi-component .NET backdoor (STOCKMARKET orchestrator, STOCKBROKER tunneler, STOCKTRADER collector) communicating via WebSocket C2 over wss:// to Glitch.me and theworkpc.com domains
  • Environmental keying: uses target hostname/domain hash as decryption key for config, preventing sandbox analysis
  • Latest wave (Nov 2025) delivers via RAR archives exploiting CVE-2025-8088 (WinRAR)
  • GitHub repo ChikenFresh/google-ai-labs-it identified hosting Python C2 controller

Actionable Intel

ArtifactTypeATT&CKLog SourceAction
wss://wool-basalt-clock.glitch.me/wsWebSocket C2T1071.001Proxy / NGFW / DNSBlock
wss://weatherdataai.theworkpc.com/wsWebSocket C2T1071.001Proxy / NGFW / DNSBlock
wool-basalt-clock.glitch.meC2 domainT1071.001DNS logsHunt
weatherdataai.theworkpc.comC2 domainT1071.001DNS logsHunt
1fc23ec18a94a599a34c74ef5f49a1e27acd37a07d5846661702b5e7e81a6a24SHA-256 (StockMarketNews.exe)T1059.001EDRHunt
9fe944147c15a87963b06baf6473288d64c23655a0ba9369c35566272d8efc73SHA-256 (docs.zip)T1204.002EDR / email gatewayBlock
dfd5cb91d06b9649d4cab500343af80ad1144a9e46641cc406f43dd169003c22SHA-256 (SMNet.exe — STOCKBROKER)T1090EDRHunt
2af7b513c05e76d7da5f75bb0a223c894a706c99ef2c2ddfe4eae542f95a08e0SHA-256 (StockMarketView.exe — STOCKMARKET)T1059.001EDRHunt
d3fd32f915c239872c9e7ed9408b1f36dfcef03aa68f9a396d05c437667cdb43SHA-256 (ClientMNGR2.exe — K1MORPHER obfuscated)T1027.002EDRHunt
98ce3c6e4dd05887ea619f2bbfeb2e2c2805ed07e85e119b79b828b7ef8be397SHA-256 (GR3.exe — K1MORPHER obfuscated)T1027.002EDRHunt
.NET process using WM_COPYDATA` IPC + WebSocket outboundBehavioralT1559EDR / Sysmon EID 8Hunt
Academic/diplomatic-themed .rdp or .rar email attachmentsDeliveryT1566.001Email gatewayBlock

Detection

SourceRuleGap
Splunk ESCUNoneNo STOCKSTAY-specific rule; need WebSocket C2 detection + .NET WM_COPYDATA IPC pattern
ElasticNoneNo STOCKSTAY-specific rule; need .NET AppDomainManager injection detection
Sigmanet_connection_win_susp_outbound_wss.yml (community, partial)Need STOCKSTAY-specific WebSocket URI pattern match

Sources: GTIG Blog · The Hacker News · The Record


2. Amazon Q Developer MCP Auto-Exec — CVE-2026-12957

TL;DR: Amazon Q Developer IDE extension auto-loaded MCP server configs from cloned repos without consent, enabling cloud credential theft via a single malicious .amazonq/mcp.json file. Fixed in Language Server 1.65.0+.

What’s New:

  • Wiz disclosure June 26 with full PoC demonstrating AWS credential theft from a poisoned repo
  • .amazonq/mcp.json auto-executed on project open — no prompt, no workspace trust check
  • MCP server processes inherited developer’s full environment (AWS keys, CLI tokens, SSH agent)
  • CVSS 8.5 — attack requires only git clone + opening project in VS Code with Amazon Q extension
  • Similar flaws reported in Claude Code, Cursor, and Windsurf around same time period

Actionable Intel

ArtifactTypeATT&CKLog SourceAction
.amazonq/mcp.json in untrusted reposMalicious configT1195.001Git pre-commit hooks / repo scanningBlock
Amazon Q Language Server < 1.65.0Vuln versionT1203Software inventoryPatch to 1.69.0
Unexpected sts:GetCallerIdentity from developer workstationsCredential abuseT1078.004AWS CloudTrailHunt
MCP server spawning unexpected child processesBehavioralT1059EDR / process telemetryHunt
Outbound connections from MCP server processes to non-AWS endpointsExfilT1041NGFW / proxyHunt

Detection

SourceRuleGap
Splunk ESCUNoneNo rule for IDE MCP config auto-execution abuse
ElasticNoneNo rule for MCP config auto-loading in IDE extensions
SigmaNoneNeed rule for .amazonq/mcp.json creation + process spawn from IDE context

Sources: Wiz Blog · The Hacker News · The Register


Status Updates

  • CVE-2026-12569 (PTC Windchill/FlexPLM): CISA KEV federal deadline TODAY June 28. Active exploitation deploying JSP webshells ongoing. Original brief.
  • CVE-2026-20262 (Cisco SD-WAN Manager): CISA KEV federal deadline TOMORROW June 29. Zero-day file write exploitation confirmed. Original brief.
  • CVE-2026-50656 (Windows Defender RoguePlanet): Still UNPATCHED — 12 days since CVE assignment, no Microsoft timeline. 7th Defender zero-day in 10 weeks. Original brief.
  • CVE-2026-20253 (Splunk Enterprise PostgreSQL Sidecar): Active ITW exploitation ongoing per Splunk PSIRT. Federal deadline passed June 21. Original brief.