Sublime Security is the adaptive, AI-powered cloud email security platform that combines best-in-class effectiveness with unprecedented visibility and control.
We’re excited to announce that Sublime has raised $150M in a Series C led by @Georgian_io, joined by new investors @Avenir_Growth, @01Advisors, @jonoberheide, and @nicoleperlroth, and existing investors @IndexVentures, @IVP, @slow, and @CitiVentures.
This year we launched ASA and ADÉ, our AI agents that autonomously triage threats and auto-adapt coverage, freeing security teams from repetitive work and delivering rapid, tailored defenses. We’ve grown our customer base 4x since the beginning of the year while maintaining zero enterprise customer churn since company inception.
This funding accelerates our vision to deliver autonomous email security that adapts to each organization's unique needs, stopping sophisticated attacks while eliminating the manual work and vendor bottlenecks of legacy solutions.
Thank you to our customers, partners, and investors for being on this journey with us.
🔗 Read more: https://t.co/6YuVmw9ZqS
The security industry has raced to claim "autonomous AI." The evaluation frameworks haven't kept up.
Join us on June 24 to cut through the noise – and build a real framework for evaluating agentic AI in security.
🔗 https://t.co/NyQPM6JzVj
#cybersecurity#agenticAI#infosec
🏆 Sublime has won Best Security Solution for Email / Communication Systems at the 2026 Security Awards!
Honored to be recognized alongside the world's leading security innovators.
See all winners 👉 https://t.co/pTgPtVQNSa
#CyberSecurity#EmailSecurity#SecurityAwards
Attackers run agentic AI workflows that phish at scale, 24/7. One-size-fits-all email security wasn't built for this.
See how Sublime gets ahead of novel AI attacks → June 23, 1:00 p.m. ET / 10:00 a.m. PT
https://t.co/LA6ngZiPZy
#cybersecurity#emailsecurity
Honored to be included in @Redpoint’s 2026 InfraRed 100 alongside so many innovative infrastructure and AI companies building the future of software.
See full list here: https://t.co/azrwICoBVP
Most conversations about “autonomous AI” focus on capability.
The harder question is trust.
We put together a new framework for evaluating security AI autonomy, including the 5 levels of autonomy and what it actually takes for security teams to hand over control safely.
🔗 https://t.co/61oG71IDWn
Excited to share that Valimail is now an official Sublime Security alliance partner! 📷
Valimail locks down outbound authentication to block spoofing and impersonation at the source. Combined with Sublime's tailored inbound detection that's purpose-built to catch BEC, targeted phishing, and vendor compromise with full transparency and control — it's a stronger defense across the full email attack surface.
Check out Valimail's announcement to learn more: https://t.co/Nn3SGgIYOj
🚨 Threat actors are now using JavaScript virtual machines to hide phishing payloads inside HTML attachments.
Sublime Threat Intelligence and Research (STIR) observed FlowerStorm operators adopting KrakVM just weeks after its release.
The campaign included:
• VM-based obfuscation
• Credential harvesting
• Real-time MFA interception
A key takeaway: advanced obfuscation is becoming easier to operationalize.
Our latest research breaks down the attack chain and what defenders should watch for next.
https://t.co/2PaLq4eQvE
#Cybersecurity #Phishing
“Autonomous” is everywhere in security AI right now.
But most products are still in the assisted or guided stage, not true autonomy.
One thing we’ve learned:
Autonomy is not a feature. It’s earned trust.
We built a framework for evaluating trustworthy AI:
- The 5 levels of AI autonomy
- How to evaluate vendors beyond demos
- Why evidence matters more than claims
https://t.co/vN6zNWLvNS
#Cybersecurity #SecurityAI
🏆 Excited to share we are finalists in the 2026 Security Awards by The Cloud Awards!
We're honored to be recognized for our work in email security alongside some incredible companies.
👉 https://t.co/thwjZXVYVD
#CloudAwards#SecurityAwards#Cybersecurity
Excited to announce: Sublime has been named a Rising in Cyber 2026 honoree! 🏆
Selected by 150 active CISOs, this list recognizes the 30 most promising cybersecurity startups shaping enterprise security, and we're proud to be recognized for our work in email security.
🔗 https://t.co/KqZMjcVb9F
#RisingInCyber #AISecurity #Cybersecurity
🚨 Quarantine Digests are now generally available for all Sublime Enterprise customers.
Security teams shouldn’t have to choose between:
❌ one-click user releases
❌ endless “where’s my email?” tickets
With Quarantine Digests:
✅ Users see what was quarantined
✅ Users can request releases directly
✅ SOC teams approve every restore
✅ Every action is fully audited
The result: Fewer help desk tickets. Faster workflows. No loss of control.
Read more: https://t.co/IPervympYj
Most prompt injection examples online are attention-grabbing, but not what we’re seeing in email security.
<1% are direct “ignore previous instructions.”
Instead: indirect prompt injection influencing AI-driven classification.
Attackers:
• embed benign-looking HTML
• dilute malicious signals
• push toward a benign verdict
Not overrides. Influence within design.
Breakdown + real examples: https://t.co/nDCuSmZN0d
#CyberSecurity #AISecurity #EmailSecurity #PromptInjection
BEC was driving At-Bay’s financial fraud losses.
Legacy tools weren’t catching increasingly sophisticated attacks.
After switching to Sublime:
• ~100% reduction in BEC fraud losses
• Detection of attacks others missed
• Deployment in <48 hours
How they did it: https://t.co/2Pm40TTbP2
AI content is everywhere.
Most “AI tells”? Noisy.
But used right, they still work.
May 13: Alex Orleans + Luke Wescott on making AI signals useful.
• Real-world examples
• Signal stacking
• Less analyst work
Register: https://t.co/J5IK2yFHeu
Sublime is now 100% channel-led.
Our partner program launches today.
Deliver agentic email security that adapts in hours, with transparent decisions and control when you need it.
🔗 Learn more: https://t.co/e6o9uJpwOE
“Sublime is one of those tools that just works.”
@huel cut email security noise fast:
• 95% fewer IT tickets
• 100% detection of targeted attacks
• Zero false positives
Read the story: https://t.co/wmvEaPQ4ZA
Executive impersonation has always worked in financial services.
AI is making it scale.
Faster recon. More convincing lures. Multi-stage threads that feel real.
So what’s actually changing?
• Why finance is targeted beyond just money
• How “skip-level” impersonation works
• Where AI is accelerating these attacks
• Defenses that still hold up
If you are protecting high-value transactions or sensitive data, this is worth your time.
https://t.co/dJoyZ5RJ1b
Sublime Security has been shortlisted for the 2026 Cloud Security Awards
Email is still one of the fastest-evolving attack surfaces - and one of the most targeted. This recognition highlights the work we’re doing to help organizations detect and stop threats with adaptive, autonomous protection.
Appreciate The Cloud Awards and our customers who trust us to secure their inboxes.
See the list: https://t.co/am0BA9NU0x
AI-generated content is everywhere.
Which makes most AI “tells” in email detection noisy and unreliable.
So why use them?
Because when applied correctly, they still add real value.
We’ll show how ⬇️
https://t.co/pcXfxCorR3