An integer overflow at a u_read_undo memory allocation site would occur for vim before patch 8.0.0377, if it does not properly validate values for tree length when reading a corrupted undo file, which may lead to resultant buffer overflows.
http://www.securityfocus.com/bid/96451
http://www.securitytracker.com/id/1037949
https://github.com/vim/vim/commit/3eb1637b1bba19519885dd6d377bd5596e91d22c
https://groups.google.com/forum/#!topic/vim_dev/LAgsTcdSfNA
Source: MITRE
Published: 2017-02-27
Updated: 2018-08-13
Type: CWE-190
Base Score: 7.5
Vector: AV:N/AC:L/Au:N/C:P/I:P/A:P
Impact Score: 6.4
Exploitability Score: 10
Severity: HIGH
Base Score: 9.8
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Impact Score: 5.9
Exploitability Score: 3.9
Severity: CRITICAL