The problem occured only once as now after over 120 days of uptime. The ASA crashed and rebooted suddenly.

There is something interesting in crashinfo file:

[...]

Region #12 [0x01543720] from #5 tback F4 dump off 0x4c

01543720: cc cc cc cc 69 00 00 00 23 01 1c a1 40 00 00 00 | ....i...#...@...

01543730: 00 00 00 00 00 00 00 00 a0 29 5a 01 64 2f 07 01 | .........)Z.d/..

01543740: 00 00 00 00 00 00 00 00 e0 d4 ad 00 80 d2 ad 00 | ................

01543750: 40 cd ad 00 d0 cb ad 00 00 00 00 00 52 65 73 6f | @...........Reso

01543760: 75 72 63 65 20 4d 61 6e 61 67 65 72 00 00 00 00 | urce Manager....

01543770: 00 00 00 00 00 00 00 00 00 00 00 00 a8 bb 2e 01 | ................

malloc_header:01543728

M-size : 0x40

M-allocd : 0x1072f64

**WARNING: ptr 0x1543720 not within (mh + 1) 0x1543748 and (ulong)(mh + 1) + mh->mh_len 0x1543788

[...]

Region #14 [ID:0x010feb38] from #12 (chunk-hdr) magic off 20

010feb38: 01 00 00 00 00 00 00 00 28 b2 07 01 00 00 00 00 | ........(.......

010feb48: 38 b7 69 01 9d c9 a3 15 00 80 ff ff 14 00 00 00 | 8.i.............

010feb58: 01 00 00 00 01 00 00 00 01 00 00 00 00 00 00 00 | ................

010feb68: 08 36 06 01 00 00 00 00 70 b7 69 01 8b c7 a3 15 | .6......p.i.....

010feb78: 00 80 ff ff 00 00 00 00 01 00 00 00 01 00 00 00 | ................

010feb88: 01 00 00 00 00 00 00 00 d8 2e 06 01 00 00 00 00 | ................

chunk_type: 0x10feb38

C-base : 0x0

C-size : 0x0

C-type : 0

C-headtail: 0x169b738

**WARNING: invalid chunk->next 0x1

**WARNING: invalid chunk->prev_sibling 0x107b228

**WARNING: ptr 0x1543720 not within chunk->data 0x0 and chunk->end 0x0

- no changes except for regular ACL changes;

- no new hadrware;

- no SSM modules.

Any ideas/clues?

Thanks in advance.