Bugzilla 2.16.10, 2.17 through 2.18.4, and 2.20 does not properly handle certain characters in the mostfreqthreshold parameter in duplicates.cgi, which allows remote attackers to trigger a SQL error.

SQL injection vulnerability in whineatnews.pl in Bugzilla 2.17 through 2.18.4 and 2.20 allows remote authenticated users with administrative privileges to execute arbitrary SQL commands via the whinedays parameter, as accessible from editparams.cgi.

Bugzilla 2.17.x, 2.18 before 2.18.2, 2.19.x, and 2.20 before 2.20rc1 inserts a bug into the database before it is marked private, which introduces a race condition and allows attackers to access information about the bug via buglist.cgi before MySQL replication is complete.

The Flag::validate and Flag::modify functions in Bugzilla 2.17.1 to 2.18.1 and 2.19.1 to 2.19.3 do not verify that the flag ID is appropriate for the given bug or attachment ID, which allows users to change flags on arbitrary bugs and obtain a bug summary via process_bug.cgi.

Bugzilla 2.17.1 through 2.18, 2.19.1, and 2.19.2, when a user is prompted to log in while attempting to view a chart, displays the password in the URL, which may allow local users to gain sensitive information from web logs or browser history.

post_bug.cgi in Bugzilla 2.10 through 2.18, 2.19.1, and 2.19.2 allows remote authenticated users to "enter bugs into products that are closed for bug entry" by modifying the URL to specify the name of the product.

Cross-site scripting (XSS) vulnerability in Bugzilla before 2.18, including 2.16.x before 2.16.11, allows remote attackers to inject arbitrary HTML and web script via forced error messages, as demonstrated using the action parameter.

process_bug.cgi in Bugzilla 2.9 through 2.18rc2 and 2.19 from CVS does not check edit permissions on the keywords field, which allows remote authenticated users to modify the keywords in a bug via the keywordaction parameter.

show_bug.cgi in Bugzilla 2.17.1 through 2.18rc2 and 2.19 from CVS, when using the insidergroup feature and exporting a bug to XML, shows comments and attachment summaries which are marked as private, which allows remote attackers to gain sensitive information.

describecomponents.cgi in Bugzilla 2.17.3 and 2.17.4 does not properly verify group membership when bug entry groups are used, which allows remote attackers to list component descriptions for otherwise restricted products.