Bug ID 690998: Validation missing when changing Syslog format from valid to invalid selection for DoS Application Protection

Last Modified: Dec 13, 2023

Affected Product(s):
BIG-IP AFM, ASM(all modules)

Known Affected Versions:
14.0.0,,,,,, 14.0.1,, 14.1.0,,,,,, 14.1.2,,,,,,,,, 14.1.3,, 14.1.4,,,,,,, 14.1.5,,,,,, 15.0.0, 15.0.1,,,,, 15.1.0,,,,,, 15.1.1, 15.1.2,, 15.1.3,, 15.1.4,, 15.1.5,, 15.1.6,, 15.1.7, 15.1.8,,, 15.1.9,, 15.1.10,,

Fixed In:

Opened: Oct 26, 2017

Severity: 4-Minor


The BIG-IP's High Speed Logging (HSL) configuration supports three syslog formats for log destinations: in TMUI syslog, in tmsh RFC5424 or leave blank as it is the default; TMUI BSD Syslog, tmsh RFC3164; and TMUI Legacy BIG-IP, tmsh legacy_bigip. The only supported format for DoS Application Protection is syslog/RFC5424. If you have not previously assigned a security logging profile to a Protected Object using a DoS Profile with the HTTP family of vectors enabled, configuration validation will prevent you from assigning a security logging profile with the incorrect syslog format. However, once the correct configuration has been made, no further validation takes place and a configuration with invalid syslog settings will be accepted. Log messages will not be sent.


Loss of logging data.


You have a Protected Object with a DoS Protection profile with the HTTP family enabled. You have an HSL configuration using a remote-syslog destination using format syslog/RFC5424, and a Security Logging profile that references the publisher in that HSL configuration. You then update the remote-syslog destination to use another syslog format.


Continue using the supported syslog format: syslog/rfc5424.

Fix Information

The system now validates that when using a Remote Syslog destination for Application DoS logs, only the Syslog/rfc5424 format is allowed.

Behavior Change

Guides & references

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