Bug ID 1137217: DNS profile fails to set TC flag for responses containing RRSIG algorithm 13

Last Modified: Nov 07, 2023

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

Known Affected Versions:
17.1.0, 17.0.0, 16.1.3, 16.1.2, 16.1.1, 16.1.0, 15.1.9, 15.1.8, 15.1.7

Opened: Aug 17, 2022

Severity: 3-Major


DNS express sends a malformed response when UDP size limit is set to 512.


Malformed DNS express responses is received when UDP size limit set to exactly 512 and a zone is signed with algorithm 13.


--The UDP size limit is set to exactly 512 and a zone that is signed with algorithm 13 (ECDSA Curve P-256 with SHA-256), the DNS express responds with a malformed packet. --Malformed responses were also seen without DNSSec, when message size is equal to the EDNS buffer size advertised by the client



Fix Information


Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips