wp-admin/admin.php in WordPress and WordPress MU before 2.8.1 does not require administrative authentication to access the configuration of a plugin, which allows remote attackers to specify a configuration file in the page parameter to obtain sensitive information or modify this file, as demonstrated by the (1) collapsing-archives/options.txt, (2) akismet/readme.txt, (3) related-ways-to-take-action/options.php, (4) wp-security-scan/securityscan.php, and (5) wp-ids/ids-admin.php files. NOTE: this can be leveraged for cross-site scripting (XSS) and denial of service.
https://www.redhat.com/archives/fedora-package-announce/2009-July/msg00676.html
https://www.redhat.com/archives/fedora-package-announce/2009-July/msg00632.html
https://www.redhat.com/archives/fedora-package-announce/2009-August/msg00608.html
https://www.redhat.com/archives/fedora-package-announce/2009-August/msg00597.html
http://www.vupen.com/english/advisories/2009/1833
http://www.securityfocus.com/archive/1/504795/100/0/threaded
http://www.exploit-db.com/exploits/9110
http://www.debian.org/security/2009/dsa-1871