KDE Konqueror 3.5.1 and earlier allows remote attackers to cause a denial of service (application crash) by calling the replaceChild method on a DOM object, which triggers a null dereference, as demonstrated by calling document.replaceChild with a 0 (zero) argument.

Konqueror can associate a cookie with multiple domains when the DNS resolver has a non-root domain in its search list, which allows remote attackers to trick a user into accepting a cookie for a hostname formed via search-list expansion of the hostname entered by the user, or steal a cookie for an expanded hostname, as demonstrated by an attacker who operates an ap1.com Internet web site to steal cookies associated with an ap1.com.example.com intranet web site.

The International Domain Name (IDN) support in Konqueror 3.2.1 on KDE 3.2.1 allows remote attackers to spoof domain names using punycode encoded domain names that are decoded in URLs and SSL certificates in a way that uses homograph characters from other character sets, which facilitates phishing attacks.

Konqueror 3.x up to 3.2.2-6, and possibly other versions, allows remote attackers to spoof arbitrary web sites by injecting content from one window into a target window or tab whose name is known but resides in a different domain, as demonstrated using a pop-up window on a trusted web site, aka the "window injection" vulnerability.

Konqueror 3.3.1 allows remote attackers to execute arbitrary FTP commands via an ftp:// URL that contains a URL-encoded newline ("%0a") before the FTP command, which causes the commands to be inserted into the resulting FTP session, as demonstrated using a PORT command.

Mozilla Firefox 0.9.2 allows web sites to set cookies for country-specific top-level domains, such as .ltd.uk, .plc.uk, and .sch.uk, which could allow remote attackers to perform a session fixation attack and hijack a user's HTTP session. NOTE: it was later reported that 2.x is also affected.

Konqueror in KDE 3.2.3 and earlier allows web sites to set cookies for country-specific top-level domains, such as .ltd.uk, .plc.uk and .firm.in, which could allow remote attackers to perform a session fixation attack and hijack a user's HTTP session.

KDE Konqueror does not prevent cookies that are sent over an insecure channel (HTTP) from also being sent over a secure channel (HTTPS/SSL) in the same domain, which could allow remote attackers to steal cookies and conduct unauthorized activities, aka "Cross Security Boundary Cookie Injection."

Internet Explorer 6.0 allows web sites to set cookies for country-specific top-level domains, such as .ltd.uk, .plc.uk, and .sch.uk, which could allow remote attackers to perform a session fixation attack and hijack a user's HTTP session.

KDE Konqueror 2.1.1 and 2.2.2 allows remote attackers to spoof a legitimate URL in the status bar via A HREF tags with modified "alt" values that point to the legitimate site, combined with an image map whose href points to the malicious site, which facilitates a "phishing" attack.