OpenSSL Communities

Disabling support of explicit curves in OpenSSL via compilation options

NT Nicola Tuveri Fri 16 Jan 2026 4:56AM Public Seen by 26

Using explicit elliptic curves defined over explicit parameters is often discouraged for security reasons, and there is a number of CVEs assigned to attacks that leverages them as an attack vector.

A new PR has been proposed to disable their support at build time in OpenSSL, and to disable it by default. https://github.com/openssl/openssl/pull/29639 is basically ready and the only remaining question is whether we should disable the support of explicit EC curves by default or not, and when.

Other communities have already chimed in:

I’d like to collect your opinion on this matter and solicit your feedback on the change and how it is going to impact your use cases.

NT

Disabling support for explicit elliptic curves

poll by Nicola Tuveri Closing Fri 23 Jan 2026 12:00PM

Using explicit elliptic curves defined over explicit parameters is often discouraged for security reasons, and there is a number of CVEs assigned to attacks that leverages them as an attack vector.

A new PR has been proposed to disable their support at build time in OpenSSL, and to disable it by default. https://github.com/openssl/openssl/pull/29639 is basically ready and the only remaining question is whether we should disable the support of explicit EC curves by default or not, and when.

Other communities have already chimed in:

I’d like to collect your opinion on this matter and solicit your feedback on the change and how it is going to impact your use cases.

Current results

Current results Option % of points Voters
Disable by default for 4.0 75 3 SK PG BB
Do not disable by default 25 1 UB
Disable by default after 4.0 0 0  
Undecided 33 MOS DS MB VM DG HK SD LC S MB NM HA KC BS MM TV AB NT NG JE

4 of 37 votes cast (10% participation)

SK

Shubham Kumar Fri 16 Jan 2026 5:03AM

Disable by default for 4.0

Given the vulnerabilities associated with malicious parameters (such as CVEs mentioned on github), it is best to disable them by default during compilation. However, I dont know if there are major use cases or applications with it either, except for the one mentioned in the distribution community by Clemens (just got to know), imo, it will be better to remove it entirely from the codebase to prevent any future attacks.

BB

Billy Brumley Fri 16 Jan 2026 11:52AM

this is legacy stuff that just needs to die. NSS stripped it out a long, long time ago

UB

Uri Blumenthal Fri 16 Jan 2026 8:54PM

ECC in general needs to die. However, as long as ECC still lives - explicit curves have their place. Let's not be too heavy-handed here. (I wanted to add that not all the users are idiots, and those that are will find a way to shoot themselves and others in the foot regardless, but you should have experienced that obvious truth already.)