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[return to "Critical RCE Vulnerabilities in React and Next.js"]
1. _pdp_+Uc[view] [source] 2025-12-03 16:58:16
>>gonepi+(OP)
I don't have time to look into it right now (def later)!

However, I was curious to see if github copilot can reverse engineer it based on the latest commits and seems that what it is saying aligns with both advisories. It pointed out that it has to do with circular reference handling which sounds to me something that can be easily overlooked.

While this analysis might be completely off, the simple fact that I could get even this information without much efforts is mind-boggling. With better setup it might be able to get more.

With AI now being common place, coordinated timely disclosure is even more important considering the stakes. It is theoretically possible to get an exploit working within minutes. Considering that we see one of these major vulnerabilities annually (and it seems to me around the same time of the year) a bad actor can easily capitalise on the opportunities when presented.

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2. rvnx+ef[view] [source] 2025-12-03 17:07:42
>>_pdp_+Uc
It's easier for a bad actor to get an exploit, than for an operator to test his own site if the upgrade succeded
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3. _pdp_+og[view] [source] 2025-12-03 17:12:57
>>rvnx+ef
An operator might not be able to upgrade at all!

Along the fixes, the advisories now need to contain detailed workarouds, firewall rules and other adhoc solutions to ensure they get quickly deployed.

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4. seanw2+pz[view] [source] 2025-12-03 18:42:10
>>_pdp_+og
I tend to agree. Cloudflare and Vercel were able to mitigate in the form of WAF rules, but it's not immediately clear what a user or vendor can do to implement mitigations themselves other than updating their dependencies (quickly!).

IMO the CVE announcement could have been better handled. This was a level 10. If other mitigations can are viable and you know about them, you have a responsibility to disclose them in order to best protect the safety of the billions of users of React applications.

I wonder how many applications are still vulnerable.

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