Bug ID 454475: TLS Handshake succeeds when the padding is incorrect.

Last Modified: May 14, 2019

Bug Tracker

Affected Product:  See more info
BIG-IP LTM(all modules)

Known Affected Versions:
10.2.4, 11.0.0, 11.2.1, 11.3.0, 11.4.0, 11.4.1, 11.5.0, 11.5.1, 11.5.1 HF1, 11.5.1 HF10, 11.5.1 HF11, 11.5.1 HF2, 11.5.1 HF3, 11.5.1 HF4, 11.5.1 HF5, 11.5.1 HF6, 11.5.1 HF7, 11.5.1 HF8, 11.5.1 HF9

Fixed In:
11.6.0, 11.5.2, 11.4.1 HF9

Opened: Mar 28, 2014
Severity: 3-Major
Related AskF5 Article:
K32147936

Symptoms

When padding is used (from TLS1.0 forward), all bytes must be set the the length of the padding or the handshake should fail.

Impact

Handshake succeeds where it should fail.

Conditions

TLS 1.0 or greater handshake with padding.

Workaround

None.

Fix Information

The padding values used in the TLS 1.0 or greater handshake are now validated, and invalid values cause an alert to be sent.

Behavior Change