6.5Medium

CVE-2026-85078

Sanic is an opensource python web server/framework. In version 25.12.0, Sanic's core HTTP/1.1 chunked-body handling does not fully consume the trailer-part after the terminating zero chunk before reusing the keep-alive connection buffer. A remote unauthenticated client can place attacker-controlled bytes in that trailer region, causing Sanic to parse and route them as a hidden second request after the outer request. This breaks HTTP request-boundary integrity and can provide a request-smuggling primitive when Sanic is deployed behind intermediaries. This issue is fixed in version 25.12.1.

What this means for your business

An attacker can use it remotely, over a network, without a login, and without anyone at your company clicking anything.
FIRST's prediction model gives it a 0.3% chance of attack attempts being seen in the next 30 days, ranking above 22% of all known flaws.

What to do

1Ask your IT team or provider whether any of your systems use the affected product.
2If you do, follow the vendor's guidance. No patch reference has been published yet.

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CVE-2026-85078

What this means for your business

What to do

Not sure if your company is exposed to CVE-2026-85078?

Scoring

Dates

References