Opened 9 months ago
Last modified 8 months ago
#2542 new defect
ssl_ecdh_curve is sometimes ignored in server blocks — at Version 1
| Reported by: | Avamander | Owned by: | |
|---|---|---|---|
| Priority: | minor | Milestone: | |
| Component: | nginx-module | Version: | 1.18.x |
| Keywords: | ssl_ecdh_curve, kex, default_server | Cc: | Avamander |
| uname -a: | 5.15.0-78-generic Ubuntu | ||
| nginx -V: | nginx version: nginx/1.18.0 (Ubuntu) | ||
Description (last modified by )
Consider a scenario when a single IP x.y.z.q has two server blocks. Both server blocks listen on the same port and support TLS. One of those blocks is marked default_server and handles the non-SNI requests.
If both blocks define ssl_ecdh_curve then it has zero effect on the non-default_server. This is done without warning.
One of the possible implications of this is that a more secure configuration is silently ignored. (I stumbled upon this when trying to enable post-quantum key exchange algorithms.)
Understandably nginx can't (currently, even though server_name could be read before KeXs come into play) respect the directive in both blocks, but in that case the ignored one should throw a non-critical warning. Plus, it could be better-documented.
