Mar 27, 2026 - For details about updated CVE-2025-53521 (BIG-IP APM vulnerability), refer to K000156741.

Forum Discussion

Najm's avatar
Najm
Icon for Cirrus rankCirrus
May 21, 2026

certitcate error

we have issue when enable new certitcate this error it observed ALPN, offering h2 * ALPN, offering http/1.1 * Cipher selection: ALL:!EXPORT:!EXPORT40:!EXPORT56:!aNULL:!LOW:!RC4:@STRENGTH * succes...
application delivery
F5_Design_Engineer's avatar
F5_Design_Engineer
Icon for MVP rankMVP
May 22, 2026

Hi Najm​ ,

 

Your issue is almost certainly missing intermediate certificate chain on F5 SSL profile

 

This error is very common when enabling a new certificate on F5 — and your curl output already tells the exact problem:

 

SSL certificate problem: unable to get local issuer certificate

 

 

The client (curl) does NOT trust your server certificate because:

 

The certificate chain is incomplete, OR

The intermediate CA is missing, OR

The client cannot build a full trust chain to a root CA

Most Likely Cause (in F5 cases)

 

Intermediate certificate NOT attached in SSL profile

 

When you install only:

 

Server cert

Private key

But miss the intermediate chain

 

Clients fail with this exact error

Let me know for any further help in fixing the SSL chain.

  • Najm's avatar
    Najm
    Icon for Cirrus rankCirrus
    May 22, 2026

    thanks for update but let me know how resolve with steps  it or share with article with steps to help me out ?