Bug ID 686043: dos.maxicmpframesize and dos.maxicmp6framesize sys db variables does not work for fragmented ICMP packets

Last Modified: Sep 13, 2023

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

Known Affected Versions:
11.6.1, 11.6.2, 11.6.3, 11.6.3.1, 11.6.3.2, 11.6.3.3, 11.6.3.4, 11.6.4, 11.6.5, 11.6.5.1, 11.6.5.2, 11.6.5.3, 12.0.0, 12.0.0 HF1, 12.1.0 HF1, 12.0.0 HF2, 12.1.0 HF2, 12.0.0 HF3, 12.0.0 HF4, 12.1.1 HF1, 12.1.1 HF2, 12.1.2 HF1, 12.1.2 HF2, 12.1.0, 12.1.1, 12.1.2, 12.1.3, 12.1.3.1, 12.1.3.2, 12.1.3.3, 12.1.3.4, 12.1.3.5, 12.1.3.6, 12.1.3.7, 12.1.4, 12.1.4.1, 12.1.5, 12.1.5.1, 12.1.5.2, 12.1.5.3, 12.1.6, 13.0.0, 13.0.0 HF1, 13.0.0 HF2, 13.0.0 HF3, 13.0.1, 13.1.0, 13.1.0.1, 13.1.0.2, 13.1.0.3, 13.1.0.4, 13.1.0.5, 13.1.0.6, 13.1.0.7, 13.1.0.8, 13.1.1, 13.1.1.2, 13.1.1.3, 13.1.1.4, 13.1.1.5, 13.1.3, 13.1.3.1, 13.1.3.2, 13.1.3.3, 13.1.3.4, 13.1.3.5, 13.1.3.6, 13.1.4, 13.1.4.1, 13.1.5, 13.1.5.1, 14.0.0, 14.0.0.1, 14.0.0.2, 14.0.0.3, 14.0.0.4, 14.0.0.5, 14.0.1, 14.0.1.1, 14.1.0, 14.1.0.1, 14.1.0.2, 14.1.0.3, 14.1.0.5, 14.1.0.6, 14.1.2, 14.1.2.1, 14.1.2.2, 14.1.2.3, 14.1.2.4, 14.1.2.5, 14.1.2.6, 14.1.2.7, 14.1.2.8, 14.1.3, 14.1.3.1, 15.0.0, 15.0.1, 15.0.1.1, 15.0.1.2, 15.0.1.3, 15.0.1.4

Fixed In:
15.1.0, 14.1.4

Opened: Sep 28, 2017

Severity: 3-Major

Symptoms

ICMP/ICMPv6 fragmented packet with size larger than dos.maxicmpframesize is not counted in stats for 'ICMP frame too large' DoS vector.

Impact

-- ICMP fragmented packet with size larger than dos.maxicmpframesize is not dropped. -- ICMP fragmented packet with size larger than dos.maxicmpframesize is not counted in stats for 'ICMP frame too large' DoS vector. -- ICMPv6 fragmented packet with size larger than dos.maxicmp6framesize is not dropped. -- ICMPv6 fragmented packet with size larger than dos.maxicmp6framesize is not counted in stats for 'ICMP frame too large' DoS vector.

Conditions

-- ICMP fragmented packet with size larger than dos.maxicmpframesize is received. -- ICMPv6 fragmented packet with size larger than dos.maxicmpframesize is received.

Workaround

None.

Fix Information

ICMP/ICMPv6 fragmented packets are now dropped if their size is larger than dos.maxicmpframesize/dos.maxicmp6framesize. Drops are counted for 'ICMP frame too large' DoS vector stats.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips