Threat reportPhishingTL-2026-4451
Train, triage, repeat: AI-assisted phishing at scale and Red Canary's hybrid AI triage agent
Train, triage, repeat (TL-2026-4451) is a low-severity phishing campaign, first published 2026-10-26. It has no confirmed attribution, affects Multiple Email, SMS, social media and SaaS/webmail users, maps to 7 MITRE ATT&CK techniques (T1204.001, T1566, T1566.002), and is covered by 9 detection rules and 7 indicators of compromise.
- Severity
- LOWAssessed severity
- CVEs
- 0None referenced
- Techniques
- 7MITRE ATT&CK
- Actors
- 0Not attributed
- Detection rules
- 9SPL · KQL · Sigma
- IOCs
- 7Indicators of compromise
Key facts for TL-2026-4451
- Threat ID
- TL-2026-4451
- Severity
- LOW
- Status
- ACTIVE
- Category
- PHISHING
- First published
- Last reviewed
- Attribution confidence
- LOW
- Motivation
- FINANCIAL
- Target sectors
- finance, retail, government administration, technology, enterprise
- Target regions
- Global
- Detection rules
- 9
- Indicators of compromise
- 7
How Train, triage, repeat works
APWG observed over 3.8 million phishing attacks in 2025, with Q2 2025 (1,130,393) the highest quarterly total in two years, while adversaries use AI to craft convincing, well-formatted phishing emails at scale. Red Canary describes a hybrid triage agent (ML, rules engine, NLP feature extraction, LLMs via orchestrated subagents) reporting 94% classification accuracy.
This is a trend and defensive-capability item rather than a single campaign. It names no CVE, malware family, threat actor or network IOC. Red Canary (author Ryan Morton) cites APWG data showing over 3.8 million phishing attacks in 2025, with Q2 2025 above 1.1 million, the highest quarterly total in two years. APWG's own counts are 1,003,924 in Q1 2025, 1,130,393 in Q2, 892,494 in Q3 and 853,244 in Q4, against 3.76 million in 2024. At this volume the article argues that no analyst team can triage unaided.
The article states that an AI tool can produce personal, well-formatted phishing emails that appear legitimate even to a trained analyst. It does not name specific tools, phishing kits or delivery mechanisms. The APWG 2025 Year in Review (published 2026-02-23) adds context: phishing and impersonation volume on social media grew between 51 and 843 percent quarter to quarter across major platforms. Finance, retail and federal government brands were most spoofed there, and social media and SaaS/webmail were the most attacked phishing categories. QR code phishing declined from Q3 to Q4 2025 as attackers moved to new infrastructure. Wire-transfer BEC attacks rose 136% in Q4 versus Q3, and APWG identified Scripted Sparrow as the most prolific BEC group, estimated at 6 million highly targeted emails per month. APWG also reported an average Q2 2025 wire-transfer BEC request of $83,099, up 97% from the prior quarter.
On the defensive side, Red Canary describes a graph workflow of five orchestrated subagents. (1) Parsing and enrichment normalizes the raw email into a standard object and adds domain reputation and abuse context. (2) Feature extraction produces true/false features through boolean logic and AI-powered NLP checks. (3) A rules engine applies deterministic, TTP-level rules before classification. (4) Hybrid classification combines a classical ML model trained on analyst assessments with LLM reasoning. (5) A transparency layer returns a category, summary and detailed explanation with every verdict. An analyst feedback loop retrains the system, and Red Canary reports 94% accuracy. That figure is a vendor claim and has not been independently verified. The publication date is not stated in the article body; a search summary reports 2026-06-30.
MITRE ATT&CK techniques used in TL-2026-4451
Execution
Initial Access
T1566 Phishing; T1566.002 Spearphishing Link; T1566.003 Spearphishing via Service
Resource Development
T1583.001 Domains; T1588.007 Artificial Intelligence
Defense Evasion
Affected products and versions in Train, triage, repeat
- Multiple — Email, SMS, social media and SaaS/webmail users
Remediation for Train, triage, repeat
Immediate actions
- Report and triage suspected phishing emails promptly using enrichment of sender domain reputation and historical indicators
- Treat well-formatted, personalized emails as suspect: do not rely on poor grammar or formatting as a phishing signal
- Apply deterministic rules for known phishing TTPs before ML/LLM classification
Workarounds
- Require out-of-band verification for wire-transfer and payment-change requests to counter BEC
Longer-term hardening
- Combine ML classification, a rules engine, NLP feature extraction and LLM reasoning with analyst feedback loops to scale phishing triage
- Return explanations (category, summary, rationale) with automated verdicts so analysts can verify them
- Extend user reporting and awareness to social media, SMS and QR-code lures
Timeline of Train, triage, repeat
- APWG recorded about 3.76 million phishing attacks across 2024, the baseline for 2025 comparisons
- APWG observed 1,003,924 phishing attacks in Q1 2025
- APWG observed 1,130,393 phishing attacks in Q2 2025, the highest quarterly total in two years; average wire-transfer BEC request was $83,099, up 97% quarter over quarter
- APWG observed 892,494 phishing attacks in Q3 2025
- APWG observed 853,244 phishing attacks in Q4 2025 (down 4% from Q3); wire-transfer BEC attacks rose 136% versus Q3; QR-code phishing declined as attackers moved to new infrastructure
- APWG published its 2025 Year in Review: about 3.8 million phishing attacks in 2025, social-media scam volume up 51 to 843 percent quarter to quarter, and Scripted Sparrow named the most prolific BEC group
- Red Canary published its phishing AI agent article (date reported by a search summary; not stated in the article body): a hybrid triage agent of five orchestrated subagents reporting 94% accuracy
Sources cited for Train, triage, repeat
- Train, triage, repeat: The AI agent changing how we fight phishing (Red Canary, Ryan Morton)
- Zscaler Blog mirror: phishing AI agent
- APWG Year in Review: Scams Explode in 2025 via Social Media, SMS, Email and QR Codes
- APWG Phishing Activity Trends Report, Q2 2025
- APWG Phishing Activity Trends Report, Q4 2025
- APWG Phishing Activity Trends Report, Q3 2025
- APWG Phishing Activity Trends Report, Q1 2025
- APWG Phishing Activity Trends Reports index
- Red Canary Builds Agentic AI Pipeline to Triage Phishing
- Red Canary SecOps Weekly: How to defend against AI-powered attacks
- Red Canary SecOps Weekly: Email security and phishing
Detection coverage for TL-2026-4451
As of 2026-10-26, Threadlinqs Intelligence publishes 9 detection rule(s) for TL-2026-4451 across Splunk SPL, Microsoft KQL and Sigma, covering 7 indicator(s) of compromise. The whole corpus is readable without an account; a free account unlocks full detection query text in Splunk SPL, Microsoft KQL and Sigma; paid tiers add raw indicator values, correlation and the MCP server. Threadlinqs MCP server · View plans.