Last Modified: Apr 28, 2025
Affected Product(s):
BIG-IP LTM
Known Affected Versions:
11.6.1, 11.6.1 HF1, 12.0.0, 12.0.0 HF1, 12.0.0 HF2, 12.0.0 HF3, 12.0.0 HF4, 12.1.0, 12.1.0 HF1, 12.1.0 HF2, 12.1.1, 12.1.1 HF1, 12.1.1 HF2, 12.1.2
Fixed In:
13.0.0, 12.1.2 HF1, 11.6.1 HF2
Opened: Jun 07, 2016 Severity: 3-Major Related Article:
K78449695
When RFC 7507 (fallback SCSV) was implemented, some BIG-IP administrators found their TLS/SSL clients were incompatible and could no longer connect to the BIG-IP system.
Inability to support connections from older TLS/SSL clients that are unable to use the more recent (and more secure) TLS/SSL protocols.
Client software that attempts to connect to a virtual server using an older, less secure version of the TLS/SSL protocol, for instance, TLS 1.0.
There is no workaround.
When SSL.fallback_SCSV is set to disable, the RFC 7507 implementation will be disabled, though it must be acknowledged that this introduces a security hole when negotiating SSLv3.
When RFC 7507 was implemented, some BIG-IP administrators found that their SSL clients were incompatible. This change introduces a bigdb variable (SSL.fallback_SCSV) to disable this.