Bug ID 2034985: Unable to forward NTLM SSO back-end cookies to front-end

Last Modified: Dec 16, 2025

Affected Product(s):
BIG-IP APM(all modules)

Known Affected Versions:
17.5.1, 17.5.1.2, 17.5.1.3

Fixed In:
21.0.0

Opened: Aug 20, 2025

Severity: 3-Major

Symptoms

Unable to forward NTLM SSO back-end cookies to front-end. NTLM has three HTTP round-trips and can set different sets of cookies in each trip. After successful NTLM SSO, APM does not forward some cookies from the back-end to the front-end.

Impact

Cookies are not sent to the client side, and SSO negotiation fails.

Conditions

-- NTLM SSO is configured. -- The server side sends one or more 401 responses to the BIG-IP system during the transaction, followed by a 200 response.

Workaround

None

Fix Information

Send relevant cookies in response.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips