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Incident March 30th, 2026 – Accidental CDN Caching

by cebert on 3/31/2026, 1:28:18 AM

https://blog.railway.com/p/incident-report-march-30-2026-accidental-cdn-caching

Comments

by: varun_chopra

The status page [1] has the actual root cause (enabling &quot;Surrogate Keys&quot; silently bypassed their CDN-off logic). The blog post doesn&#x27;t. That&#x27;s backwards.<p>&quot;0.05% of domains&quot; is a vanity metric -- what matters is how many requests were mis-served cross-user. &quot;Cache-Control was respected where provided&quot; is technically true but misleading when most apps don&#x27;t set it because CDN was off. The status page is more honest here too: they confirmed content without cache-control was cached.<p>They call it a &quot;trust boundary violation&quot; in the last line but the rest of the post reads like a press release. No accounting of what data was actually exposed.<p>[1] <a href="https:&#x2F;&#x2F;status.railway.com&#x2F;incident&#x2F;X0Q39H56" rel="nofollow">https:&#x2F;&#x2F;status.railway.com&#x2F;incident&#x2F;X0Q39H56</a>

3/31/2026, 3:05:39 AM


by: stingraycharles

This write up doesn’t make sense. Authenticated users are the ones without a Set-Cookie? Surely the ones with the cookie set are the authenticated ones?<p>There are dozens of contradictions, like first they say:<p>“this may have resulted in potentially authenticated data being served to unauthenticated users”<p>and then just a few sentences later say<p>“potentially unauthenticated data is served to authenticated users”<p>which is the opposite. Which one is it?<p>Am I missing something, or is this article poorly reviewed?

3/31/2026, 2:31:37 AM


by: rileymichael

pretty hard to find this on their blog, looks like incidents are tucked away at the bottom. an issue of this size deserve a higher spot.<p>(also looks like two versions of the &#x27;postmortem&#x27; are published at <a href="https:&#x2F;&#x2F;blog.railway.com&#x2F;engineering" rel="nofollow">https:&#x2F;&#x2F;blog.railway.com&#x2F;engineering</a>)

3/31/2026, 4:13:12 AM


by: muragekibicho

Does Stripe use Railway? The dashboard was down today and this is the only incident report I&#x27;ve encountered and the timeline matches Stripe&#x27;s downtime.

3/31/2026, 4:06:31 AM


by: sublinear

I&#x27;m curious if having unique URLs per user session would mitigate this.<p>I think that&#x27;s already best practice in most API designs anyway?

3/31/2026, 2:33:34 AM


by: wokgr3t4

[dead]

3/31/2026, 2:46:26 AM


by: sebmellen

Almost three years ago now, Railway poached one of our smartest engineers. They were smart to do so. I have a lot of respect for the Railway team and I’m impressed with their execution.<p>I think this is their first major security incident. Good that they are transparent about it.<p>If possible (@justjake) it would be helpful to understand if there was a QA&#x2F;test process before the release was pushed. I presume there was, so the question is why this was not caught. Was this just an untested part of the codebase?

3/31/2026, 2:57:03 AM